Cheating Husband

I found out yesterday my newly wed husband of 3 weeks has been cheating on me the last 3 months of our relationship. He has an oral fixation and I do not due to bad experiences with someone else. He said because I wasn't going down on him as frequently as he wanted me to, he found someone that would (his ex of 7 years). I was and am so heartbroken that I have bent over backwards for my husband and I have financially supported our family the entire time just to find out everything has been a lie. He said he wants to try and work things out with me and stay married. I told him that everything with her stops. (They have 2 kids together). I told him from now on there will be no more going to her apartment to pick up and drop off the kids. They need to meet in a neutral public place so there is no temptation ever again. He agreed. So last night I gave him oral and after he finished, I burst into tears. I couldn't help but think she was the last one to do it for him. Same thing happened this morning. So with my story being told, am I crazy for wanting to save our marriage? Do yall think he will stop seeing her? How do I get past this?