How do I get my confidence back?

i used to be really confident and outgoing but since I had my son 2 years ago and subsequently split up with his father 18 months ago, I have lost all confidence when it comes to dating and men. I have been on a handful of dates and i have no problem attracting men but for some reason when it comes to the point of becoming intimate or even kissing, i clam up and get really scared. Even though I know i am quite attractive, for some reason I just feel like I would never be good enough for anyone and I have a list of insecurities about my body which are really holding me back from getting close to anyone. The thing is I just don't get where this has come from cos i've always kind of looked the same and if anything im probably looking better than I ever have, but I just seem to have completely lost faith in myself not only physically but I just feel sh*t in general like no one would ever want me especially because I have 2 children. I just wish I knew how I could get "the old me" back again?? recently on a 1st date I actually cried because the guy tried to sit close to me and put his arm around me even though i REALLY liked him that kind of made it worse because I was so attracted to him i panicked because i felt so ugly.. this it nuts I know deep down this is crazy but i just don't know how to stop feeling this way. I just push everyone away who tried to get close. any suggestions????