I never thought my H would have an affair...words uttered by almost all of us...and yes, you should rethink whether or not you might end up with problems you didn't count on from him...I know that is one major reason that I have kept a LS or D filed since H left me (he has returned but financial issues make it necessary now)...
I want to emphasize that just because all of this is happening it doesn't mean that your H has changed for the worse permanently and can never be trusted again...just during this process...MLC or whatever his issues are...you need to protect yourself and your children...proactively protect...