I think that you can see, especially on this forum, that there are a lot of overweight women - some who are bigger than you - who have boyfriends and husbands, so it's not necessarily because you're overweight. also, i know EXACTLY how you feel, because i used to be like that. in my late teens and early 20's, i was about 230lbs and had never had a boyfriend. only super creepy guys would ever hit on me, and i turned them away. i didn't want anyone to touch me cuz i was grossed out with myself. and the older i got, the more embarrassed i became with my virginity and i wished someone would just come and take it away so i could get it over with, but it was just a vicious cycle.
see, the thing is, it actually has nothing to do with size. having men being attracted to you depends solely on your confidence level. and when you don't have any, you don't attract anybody; or you attract creeps, because they can't read the signals that you're unconsciously sending out. when you start feeling more confident with yourself, i SWEAR, guys will start paying attention. a few years ago, before i met my current boyfriend, i was in a bit of a "flirt" phase and i was feeling like i was basically "hot sh!t" and everytime i walked into a club or a bar, i would have guys hitting on me left and right, and i LOVED it. lol. i was nearly 200lbs. in a country where the average girl weighs about 90lbs. so i can tell you, it definitely has nothing to do with weight.
the funny part is, now that i'm madly in love with my bf, even though i'm loads thinner (and cuter!) i hardly get hit on at all!! lol. so in my mind, it's all about the vibes you send out, and that's not a conscious thing. when you are a confident single woman, that seeps through and guys find that attractive. now, i'm pretty sure i'm sending out "i'm taken so don't even bother cuz you will crash and burn!" vibes, so i don't get hit on at all... lol.
also, eye-contact is a huge thing. when i was younger (and bigger) if my friends ever managed to drag me out to a club with them, i would sit in a corner and not look at anybody. if i saw a guy i thought was hot, i would avoid eye contact at all cost. i was thinking "he'll know i like him if he catches me looking at him!!" what kind of stupid way of thinking is that?!? don't i want him to know i like him? when i was in the flirty phase i mentioned above, i looked everybody in the eye and i smiled at them. i saw a hot guy walking down the street? i made eye contact and smiled. sometimes he'd stop and come over to chat, most times he'd just smile back and that would just make me feel good about myself.
the thing is, when you see these messages all around that say "you have to love yourself first", it's not crap. it's true. and i know it may seem hard now, but until you love yourself, ain't nobody else gonna come and do it for you. i mean, you can have a 200+ lbs girl who's a hit with guys and really happy with her life because she's at ease with herself, and you can have a 110lbs girl who is just as miserable as you are, because she has terrible self-esteem and she in her head thinks that she is unworthy of being loved.
of course, there are some stupid jerks out there who are only into the barbie-doll-type chick, but those are not guys you wanna date anyways. the average male will be attracted to confidence, and boobs
good luck, and cheer up, kid! <3
PS: i can see from your profile pic that you have a super cute face. once you are feeling confident with yourself, you will have guys lining down the block to date you