Hi there guys!

Sorry for the long post! :/

About five months ago, my fiancé started meeting someone else with whom she had "a connection". She was suffering from depression and this other person "could perfectly understand what she was going through". This made me jealous of that person because I thought I was going to lose her, because she would leave me for someone that could understand her better than me, with whom she shared many more feelings and thoughts.

I started losing weight to look more fit (like the other girl) and behaving like her to look more appealing. My only thoughts since then have been to make my fiancé feel as lonely, abandoned and worthless as I felt back then. It's like she was so into this other girl that she couldn't see beyond that, she couldn't see how I was feeling and I was feeling so... unimportant? I felt as if my girlfriend only wanted to be with this other person all the time, I would get paranoid every time she checked her phone (she started doing it more than usual), she would invite her over to have dinner when we were supposed to have dinner by ourselves, she started cuddling with her even when I was in the room with them, and I just felt exhausted, betrayed and completely replaceable.

I've tried to forgive and forget because I know it was tough times for her and it was no more than a friendship, but I am still not over it and extremely mad at her for trusting that other person more than me or telling her about her suicide attempt before I even knew.

The feeling of making people feel bad about themselves when I feel bad is not something from now, it's been happening to me since I was a little kid, and I feel good when I do it, but then, the next second after that, I feel like a piece of garbage. I am dealing with some issues now and I've come to realize that this way of treating people has never stopped and that deep inside I'm still behaving like the kid that would hit other children in the bathroom to comfort them seconds later while telling them everything would be alright.

I also feel very possessive over her and it scares me that I'm going to lose because of my "weirdness" and jealousy. If I feel like I'm being to possessive or jealous, I get really angry and I feel the need of hurting myself as a way of coping, otherwise it's like my head could literally explode from the extremely loud thoughts of "you're not enough" and "you're an extremely toxic person and you deserve everything that's happening to you". When I get to that extreme, I literally start getting super anxious because I think the only way I have of stopping those thoughts is by physical pain or even just dying.

I think I should also point out that I am experiencing a lot of dissociation lately, almost every day and for the entire day sometimes (I've always experienced dissociation in a regular basis, but I don't know if it's become more regular now or I am just more aware of it).

People usually say I'm a very selfish person and that I have the level of empathy of a fish. I am a very solitary person and it's extremely difficult for me to make friends, so the only person I can rely on right now and I can fully trust is my fiancé and I'm super scared of losing her, so that's why I'm reaching out for advice.

Of course, this is much more complicated that I can express in just a post and I feel so many more things that make myself question who I really am, but I would appreciate any kind of advice or help (FYI, for two weeks now I'm seeing a therapist but I haven't told him about this yet).

Thanks!