Events like this aren’t totally unusual. In 2010, employees at the Discovery Channel headquarters in Silver Spring, Maryland were subjected to a terrifying situation when a man stormed into the building armed with a gun, taking three employees hostage. After a four-hour standoff, he was killed by police. The man, who was apparently mentally unstable, was reportedly upset with the channel’s environmental programming.

That same year a man whose mother was being treated at Johns Hopkins hospital in Baltimore allegedly reacted to upsetting medical information by shooting a doctor, then killing his mother and himself. One of my friends was working in the hospital that day on a psychiatric unit in a different part of the hospital from where the shooting took place. She and her coworkers continued to take care of their patients while aware of the dangerous situation unfolding just a few floors away from them. I texted her to make sure she was safe, and she confirmed she was. The next day employees of the hospital just returned to work like usual.

While these examples are undoubtedly tragic, there are many other kinds of everyday traumatic events that we can experience at work—and they can have as much impact on us, even if they aren’t as dramatic or horrific.

Working with a terrible boss can be traumatic, for example. So can having a coworker who bullies you or someone else you work with. Sexual harassment or other types of employment discrimination can certainly be traumatic. Even layoffs or a company’s financial uncertainty can cause employees to exhibit trauma reactions.

All of us have experiences from our childhoods that influence the way we connect with other people as adults. We learn how to get along with others from our childhood friendships and sibling interactions. Our models for romantic relationships are colored by the communication and conflict styles we saw demonstrated by our parents or primary caregivers growing up. And any traumatic events we experienced can affect us over our whole lives, regardless of how long ago they occurred, if the trauma is unresolved. Quite frequently, problems at work exacerbate underlying trauma from childhood, and this is what prompts people to come see me for therapy.

We act out the roles from our families of origin in all of our relationships.

Susan liked her new job at the financial services firm. She felt confident in her abilities, and she liked most of her coworkers. The office was small, and several of the women had been working together for years. For some reason, though, one colleague, Angie, wasn’t warming up to her. Susan couldn’t tell why Angie didn’t seem to like her, but she told herself not to worry about it, that she should just focus on doing the job well. But as the weeks went by she noticed that Angie often ignored her in the break room when they were on lunch breaks, excluded her from social events outside of work while inviting the other women in front of her, and seemed to make efforts to undermine Susan.

She began to feel less confident and more self-conscious, whether or not Angie was around. And she questioned whether she was imagining things, since no one else seemed to notice or acknowledge Angie’s behavior.

One day, in front of her peers and Susan’s boss, Angie yelled at her and blamed her for a mistake that Susan had no part of. Susan froze and stammered while attempting to defend herself, fighting back tears. For the rest of the day Susan struggled to hold her head up at work. She felt like she was being unfairly targeted, and wasn’t sure if everyone else working there thought she deserved this treatment. Why wouldn’t they speak up for her? She wasn’t sure who to trust.

Even though some of her coworkers were nice to her when Angie wasn’t around, they seemed intimidated by her behavior too. When Susan told her husband what happened, he reminded her that their family really needed the income from Susan’s job and encouraged her to ignore this woman. Susan felt like she was back in high school, carrying her lunch tray to a table and trying to sit down while being shunned by girls who would not allow her to join their group. She felt alone, misunderstood, and confused. Part of her knew that Angie’s behavior was bullying, and that in addition to being unprofessional, it was also a human resources issue. At the same time, she feared that if she went to HR, Angie would find out and retaliate against her.

She began making mistakes at work because she was so preoccupied with avoiding Angie’s wrath. This made her feel even worse about herself. She fantasized about quitting the job she had previously enjoyed, but felt stuck, worrying that no one would take her seriously, and she was trapped by financial constraints. Finally, Susan did go to HR. They hinted that others had had problems with Angie in the past, because “Angie just doesn’t like new people.” They suggested Susan confront Angie directly, and show her that she was not intimidated. But Susan was intimidated, and didn’t feel like she could do that.

Angie’s bullying was bringing out a very timid, fearful side of Susan’s personality: She felt really lost. And without the company’s support, Susan felt betrayed and even more alone. She decided not to ask for help again, instead pretending nothing was wrong. She muddled through as well as she could for about six months, when a new person was hired. Suddenly Angie included Susan in the group and the new person became the target of Angie’s bullying. Susan was so confused—she was glad to be accepted by the group, but she felt complicit in Angie’s bullying of the new person. She tried to keep the peace with Angie, but she never trusted her, and she did not feel comfortable advocating for the new person when Angie mistreated her. Surprisingly, Susan started having nightmares and trouble sleeping when Angie stopped bullying her directly. She was troubled by weight gain and her hair began falling out.

Susan’s reaction to the trauma of being bullied by Angie had echoes of her childhood experience of being excluded in the school cafeteria. In both cases she questioned whether she deserved to be mistreated in this way, felt afraid to speak up about what was happening, and felt betrayed when her efforts to seek help were met with a tone-deaf response.

Susan’s childhood trauma was re-awakened by her experience with a workplace bully, but she didn’t realize it. If she’d been able to understand that this echo was the reason Angie’s behavior was affecting her so intensely she may have felt better equipped to address the situation. As it was, her trauma response caused her to freeze and feel powerless. As she attempted to deal with this on her own, she suffered significantly. Her emotions began to affect her health.

Trauma—whether it’s the fresh kind I saw after the Navy Yard shooting, or reactivated like Susan’s—can make itself known in different ways. The most common manifestations of PTSD are hyperarousal, re-experiencing, and numbing.

Sometimes you might feel hyperalert, watchful, on guard at all times, be easily startled, feel a general sense of anxiety, be unable to relax, and even have panic attacks. Hypervigilance often shows up as trouble falling asleep or staying asleep, anger, irritability, agitation, or difficulty staying focused and memory issues.

Re-experiencing can show up as intrusive thoughts or memories of the incident that come to mind when you don’t want them to—including flashbacks where you feel like you are back when the incident happened, watching it happen as though you are watching a movie.

Numbing can be the most difficult symptom of PTSD to recognize. People often describe feeling detached, disconnected from others, in a bubble, on the outside looking in, or on autopilot.

A sense that you can’t connect with your emotions or the feelings in your body is common. People will say that they feel nothing or dead inside. It’s also common to have less interest in things that used to be important to you and to avoid talking about or dealing with the traumatic event.

Not everyone who lives through traumatic situations will develop the symptoms of PTSD, but even if we don’t fit a diagnosis, we are all affected by traumas we have experienced. And trauma can affect us at work more often than you might think.

Frank’s childhood trauma came back to haunt him at work. As a firefighter, Frank often arrives on the scene after bad things happen. People get hurt, sometimes in fires, but more often he is responding to drug overdoses, traffic accidents, and other crisis situations. He tries to remain detached, but seeing kids who are suffering in some way is intolerable for Frank.

When he was growing up, Frank’s dad was an alcoholic who, when drunk, would beat his mom. Frank used to get in between them, trying to protect his mom from his dad’s violence. Sometimes he got hurt, but he never gave up trying to step in when his dad threatened to hit his mom. He always wished he could have had a better relationship with his father, even though in some ways he hated him for what he did to his mom when Frank was a kid.

Now that Frank’s 48 years old, he wishes he could forget about those childhood experiences, but memories keep popping up when he doesn’t want them to. He has nightmares, trouble sleeping, frequent fights with his wife, and he regrets that he’s often too angry or depressed to enjoy spending time with his kids when he’s not working.

But it’s those situations with the kids he sees in trouble that send him to a dark place. He feels like a child again, powerless to help despite his deep desire to make things better. At work he often becomes frustrated with his fire chief, who he used to put on a pedestal. Lately he feels disillusioned with the chief, feeling that he isn’t there for him the way Frank needs him to be. Although he and his fellow firefighters are supposed to be like brothers, he feels that nobody understands how he feels.

He’s never told his coworkers how he feels when he sees kids in trouble. None of them talk about their feelings, other than to tease each other for not being tough enough. And Frank? He teases the loudest, because he doesn’t want anyone to see how much he’s hurting.

Laura Reagan, LCSW-C, is a Baltimore-area clinical social worker, trauma therapist, and host of the Therapy Chat podcast.

Names have been changed to protect patient confidentiality.