Thanks all for the help and see your points that I shouldn't do anything until we figure this out. I did want to mention that the other woman knows I am married. She is also a mother but is single. I don't know the situation (i.e. divorced, never married, etc) but I do believe she would understand of all people what a non-traditional household would be like.

I'm 34 - perhaps this is some sort of crisis. I am just surprised this is happening now and with this person despite the marriage not being on great terms before this new woman. My mind is working so strangely right now.

Thanks!