Help with divorce

I read about people divorcing after surgury but never thought it could happen to me. I am 1 1/2 years out and have lost 114 lbs. My husband was always the most supportive guy and always loved me the way I was. I found out last month he is seeing a 19 year old from school and he told me with no notice that he isn't in love with me anymore and wants out. We had, what I thought, was a good relationship. We were even trying to have a second baby up until this. He only did this after I found out by accident he cheated. Now he tells me part of why is because "I have changed" since the surgery and if I had it to do over, he wouldn't want me to have had it. We have 3 yo son and my husband won't even try and work on our marriage. He is still seeing the other girl and including our son in some of the outings against my wishes. I know there are many other bigger reasons why he is doing this besides the surgery but can anyone out there tell me how someone can just "stop loving" someone else and walk away from an 8 year realtionship and a 3 year old son? I am devestated...I am seeing a counselor and lawyer but this has happened so fast I can't breath....I can't make it through the day without crying...I just can't believe this is happening....any advice??? Thanks

Ok. I have heard from you about how your husband has changed, and how he says you have changed. What have you been doing since WLS that would cause him to say you have changed? My wife is also 1 1/2 years post op and we have had are share of blowouts because of her weightloss but seem to work it out. So what I am saying is have you been going out more? More assertive towards him in what you want? Have you spent more time on the OH message boards then with your family? Not that I am saying you have done anything wrong I just like to have all the facts before making a judgement. As for him adding your child to the affair he is having. There is no excuse for that.