Fear of Excitement

Hello there guys. The title might sound weird but getting excited in any way scares me. Jumping to the background story, I just survived a relationship to which I gave almost my everything. I loved the person too much to be described in words. Too much that every words of theirs would affect me physically and emotionally. Now that the relationship is over, the person showed me their toxicity after some time in the relationship all of a sudden, I feel it very hard to cope up with normal life. For me, excitement is a feeling that was closely associated with love including the person. Now that it's over, I'm trying hard to get back a hold of the things in my life, to feel joy in little things, I often feel excited. For instance, to go for a trip or to meditate or simply to hangout with the friends. And once I feel excited, things take a u-turn, I remember them, all that time and finally I get paranoia, panic attacks and all the more anxiety. It's getting so hard for me to enjoy little things in life without feeling crushed again.