Why can't an average guy get a girlfriend?

All the guys in my class have/had a girlfriend in their life but not me.they have all kissed,but not me.I'm 5'10' and 140 lbs,am I too fat?If not,any tips to get a girl?=/

maybe it is not your time to have a girlfriend. but just try to be yourself.

You don't sound fat. People are different; that's just the way it is. Not everyone is going to get a partner at the exact same time. All you can do is wait until the time is right for you. There's no sure way to speed things up.