I CAN'T EXPLAIN IT BUT IT'S REALLY HURTING ME....?

I just came from my friends graduation barbecue an I we had a good time until the last bit, i asked my parents to let me stay to later but i shouldn't have because my friend was celebrating it jointly and my other friend had came with her fianc�e and they had came to town from college so i stayed longer and i shouldn't have because they were both snuggled up with their boyfriends/fianc�e, while it was just the FIVE of us out there. i was just standing their and they were kissing and hugging and i had to pretend to be texting looking like an idiot.and then i called my other "best friend" to stay occupied and then she tells me i cant talk right now im caking with my boo, so i felt even worse. BUT heres the twist....... I don't want a boyfriend men always hit on me especially at work and at college( I'm 19) i even forced myself to let a guy have my number it's not that their ugly its just that im not comfortable around men and when i kiss them its like .........."i wished he leave me alone and get off me." im just confused its crazy because at night i have this picture perfect fantasy about being with a woman and being happy and snuggling with her like my friends do with their men. its not that im jealous of my friends relationships because i could easily obtain one with a man also but........ I'm not into.. I'm not.......... but at the same time im jealous because i don't know.... its not like the men are ugly their actually quite handsome but.....i don't feel right i don't know whether its my insecurity or body issues (which are a problem that i have) or its just not for me? can you help me out please what am i feeling? also sometimes i say to myself when i lose weight im going to seek a relationship ,but right now with my weight i feel stuck im not Fat but i am thicker than usual? is that something that could be attributing?