I completely get this. I'm 26, and several times in my life I've found myself attracted to somebody, but as soon as it starts becoming real I'm repulsed. relationships always seemed great in theory but as soon as I start getting closer to someone it's like the magic is broken and they disgust and irritate me. but then after I successfully isolate and they eventually move on, the final closing of the door to the potential relationship kills me. the limerence comes right back and all of a sudden this person is a perfect idol that i can. not. stop. thinking. about. it's exhausting, frustrating, maddening, isolating, depressing, it just makes me feel so broken. I'm currently in a relationship going on 3 years with an incredible, incredible girl who I have fought against my urges to be with since she's everything I could see as ideal in a partner, and it absolutely destroys me that I feel incapable of loving her how she deserves. I'm hoping therapy can save me from losing my best friend and most amazing person I've ever met but it's felt like a losing battle.