Why does seeing a picture of my ex make my stomach turn?

When I see a picture of my ex my stomach turns and I sometimes have to go to the bathroom. It's like a nervous feeling. Why? I was never able to trust him and sometimes I got that nervous feeling from him when we were dating too.
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+1 y
He wasn't respectful towards me and he lied a lot and placed sexual pressure on me. I think he has narcissistic personality disorder and he was a bit older than me. I got very attached to him so it was hard to leave but I blocked him on my phone.
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+1 y
We don't talk and I feel calmer without him because I just didn't trust him and when I was with him I felt attached but sick at the same time. We did have some good times and it was an awful mindfuck of a situation. I've been to therapy about it.
Why does seeing a picture of my ex make my stomach turn?
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