Your marriage can recover, however she needs treatment. This isnt something you just "get over". She needs meds and she needs to stay on them. AS for the affair, i have said before and i will say here again, us bipolars have precious little self control. When the compulsion hits, it hits very very hard.
WIth treatment she can have a great life, however it is dealing with meds and the side effects that hurts a lot of us. But she has to SEE it for herself, if not than this will happen again and again.
Here is hoping you feel better soon, and that you and your family find their way back to a good place. It can be done, but it is a lot of work and painful.
IT will get easier to deal with, just dont make any rash, life altering decisions right now. Just concentrate on healing and day ot day stuff. What is done is done, so make sure you get some help for yourself also.
Here is to hope.