Struggling with past trauma and feeling invalidated

I had a very stressful talk with my therapist today about a lot of past trauma involving one specific person in my life that I hate to bring up. It sent me back and that's all I have been focused on all day. The reason I brought them up is because I saw this person Monday and they came over to talk to me which sent me into panic mode which my friends noticed, they tried to block this person out as much as they could and I thank them so much for that, it's just this person would not stop and it sent me back to all of the horrible shit they did to me. But every time I look back on this trauma that they have given me I feel like I don't deserve to feel traumatized by something like this, I feel as though I should just suck it up because it could have been way worse. I feel like my feelings aren't valid even though I know in the back of my mind, they are. Sorry for the rant I just needed to let it out.