I predict that this will blow over. In the cold light of day, 7 years is an investment of time that neither of you will want to ignore.
The only mistake that can be made is for you to go out with W's friend out of spite.
Sure, there may be chemistry with W's friend. Big deal. I have chemistry with a couple of women here at work...I could date them, or even have a relationship, but I don't take it past harmless flirting. Why? Because I won't until I am 100% sure my wife wants nothing to do with me or a future together. I cheated on my wife 12 years ago...dating someone would only show her "once a cheater, always a cheater". She needs to know I am a safe bet to come home to. Even if she is acting flaky right now.
Fish, you need to cowboy up and not give up so easily. You should especially not give up your hard-earned turf, ie: YOUR HOUSE.
Go back, apologize for flying off the handle, say you're still adjusting after 6 months, and you and her need to slow down and take it easy. You can't storm out the door every time you have a disagreement! Take the high road and be the better person...at least for now.
Me: 54 Her: 50 and sexy as hell M: 32yrs T: 34yrs Bomb: Sept 26-07 "lost our emotional connection" Bomb 2: Dec 25-07 she's "not feeling desire" She asked if she could come home Apr 26-08! Everything's GREAT!