Man I was having the same problem.
I was obsessed with exes of my
GF's. I was fuckign angry and get sad and all kind of other supid shit. Even though I knew that I'm the fucking PRIZE. And it bothered me even with girls that had less sexual experiences than me. It was driving me crazy.
When I was having a harem with 4 girls in it, it didnt bothered me a bit. But whenever I was in a
LTR it was driving me crazy.
So I fixed it in that way that I turned my
LTR in a
MLTR in a way. Sounds funny but it works.
I found out that I was feeling jealous because I wasnt secure in myself. So I started satrt treating my
LTR girlfriend as I was with her in
MLTR but just that she was the only one. I didnt cheated and I didnt go on real dates, but I was still talking/flirting with girls and ''trying'' to pick them up, just so I get to see that I can get other girls. That filled my need for insecurity. It's a short-term solution. But I got the time to work on my
inner game and my confidence.
But I wasnt doing this behind my
GF's back. I told her whenever I wanted to flirt with some girl or to go on a drink with some girl. I didnt told her that I went to a ''date'' but she knew where I was and what I was doing. So there was no cheating involved. If you want other girls dont get in a
LTR doooooooooh.
And your
GF HAS to trust you. If she doesnt...fucking dump her anyway dooooooh.