Looking for a Tony/Steve fic that becomes a Tony/OC

[rbbythesea.livejournal.com]

Tony and Steve are married, and Steve cheats on Tony with Rhodey, and Tony is blamed for their marriage breakup.  It's a series of fics, I think a total of three.  I read them, and then must not have bookmarked them, because I just went through all of my Avengers bookmarks and couldn't find it.

I thought it might have been a Big Bang story, but couldn't find it there either.

I am sure I read it on AO3.

Thanks for the help

Found, link in comments.