What advice would you give to this guy if he were your "friend"?

(A little background information first) - My boyfriend has a close friend that I've known for years. I actually knew him before I met my boyfriend from high school, but we didn't talk much. He asked me on a few dates, and I declined, because he wasn't my type. He was very hurt and offended by my rejection (even though I POLITELY declined) and he seems to have held it against me ever since. It's been five years. I'm still with my boyfriend and he's still close with this guy. He tries as hard as he can to be a jerk to me. He's always a smartalec, and he's always trying to prove me wrong. I don't let it get to me, I just ignore him and move on. I decided to give you that background information, so that you will understand why I'm reluctant on being "helpful" to him. He has recently been texting me, asking for advice. He's trying to hook up with a girl I used to know, which failed terribly, and now he's trying to get with a girl he works with. He's always asking me how he should approach them, and each time after he fails, he asks why, WHY does he keep failing at getting a girlfriend. Well the truth is....he's extremely obese AND his standards are WAY too high. And he's completely oblivious to this fact. Obviously, I won't tell him that's the reason he can't get a girl, but what SHOULD I tell him? I'm not saying obese people can't get love, but his standards are ridiculous. He keeps going for cute girls that are 5'4 and weigh 120, and he's 5'11 and weighs around 340. Is there a way to nicely tell him to lower his standards and maybe he'll get a girl? Or should I just keep pretending it's the girls fault when they don't accept his offer?