My husband has just told me he doesnt want to be with me anymore because I'm turning into my mother?

We have been married for 20 years in sept and together for nearly 25,we have 2 children of 16 and 10,our 16 year old is autistic but as autism goes mostly ok. 8 years ago I had an affair,for 6 months ,when he found out he was totally devastated,but it took me 7 years to admit to everything for whatever reason,10 days ago I found out he had been seeing someone else for 3 months,started as friends but he had started to have feelings for her,as soon as I found out I took over everything,closed his facebook account,wanted to see his phone bill etc,but I didnt go mental or anything,instead we had great ,he told me everything,answered all my questions and I thought all would be ok,draw a line and start again,today he blurted out that he isnt happy and hasnt been for ages and hes just trying to kid himself that all will be alright,he has gone to a friends house to do some work there for the next 3 days and I am left totally devastated,I love him so much and he says he loves me just dont know what to do for the best,I'm giving him time and space and I'm hoping I can change from the domineering person that apparently I am to save my marriage,please help me