is infidelity common in BP spouses? for some - i agree

If so, does that make it right? nope. It also this does not seem to be a "BP infidelity" situation. - i agree

Does bipolar get worse as you age? Is it progressive? Can BP 2 become BP 1? I think BP changes with age - i think so too, it can turn into bp1.

Does multiple cycling of being on meds then off then back on make it worse? Cycling does make BP worse. It has to be up to her to take the medication. - i don't know anything about this, stopping and starting meds.

i don't really feel sorry for you, you've known she had bp for 10 years. i guess you didn't know you need to learn about it. but sounds like the trust is broken for you and you've grown apart. your therapist can help you sort out what you want to do, stay or go.