Anxiety and paranoia will ruin me

Long story short, my boyfriend was one of those fuckboys that you really don’t want anything to have with until we hooked up. At first, I was really scared and kinda expected our relationship to end very fast because of his behavior towards previous girlfriends...but it really was different. He really did change and told me it’s all because of me and that he had finally fallen in love, he wants to be a better person and all that perfect stuff... I love him so much, I fell in love with him even 3 months before we finally hooked up and I feel like my loves only getting stronger and stronger... I met his parents, they are very nice and I believe they really like me.

Currently we are dating 7 months and I still have panic attacks and still am paranoid like at the beginning of our relationship... When he doesn’t text me back fast I always think the worst, sometimes I even cry when he likes other girls pictures, then I also cry out of nowhere because I see slightest change in his tone and I assume that we are going to break up and that this fairytale is going to end. It’s like living in constant fear and never being relaxed. Why am I like this? I am so scared of losing him and i always think that all this is too perfect to be true...