Finding my thoughts so hard to deal with

A quick run through. My first husband had an affair after being together 8 years.... While trying to heal met my second husband who I thought was my soulmate and we would never part. Out of the blue he left me last March, two days later he moved in with the ow! he met whole at uni and I was supporting him everyway possible. 
Im struggling to cope with the fact they are still together, they are using his money he got for the sale of the home to travel all over the world. In between uni! 
it's difficult to deal with. It came out the blue and ten months later I'm still trying to deal with it. The hurt is something I can't even begin to explain. I still feel physically sick, cry at night, back on happy pills...... 
I can't cope with them splashing around how happy they are when he has left me in so much pain? He was the love of life! However could he? 
Everyone says he is in a uni bubble, and I was just in his way right now. 
What annoys me is.... I wouldn't take him back as he has treated me so bad. So what do I want? Why can't I move on? I hate thinking about them both all the time. It's driving me crazy.