I read this one yesterday ... thought about replying but did'nt ... gave it some thought and came into work and the page was still up on my computer so I figured ... why not.
I do think you are in a tough spot as most the people here are of the mindset to "save the marriage" by saving ourselves first.
So I have been in my sitch for some time .. what .. 1.5 years now that we have been separated. W and I have not had sex 3 years up to that point. Lets say a good 3-5 years of a problem filled marriage. I think one of the lessons I have learned is that when you focus on one thing it becomes larger and has the ability to consume you. A few years ago I was convinced that the lack of sex was the issue in my M, well to be honest after reading and looking at myself in the mirror the sex was a result of a troubled marriage not the cause. And I am happy to report that I am still alive and well after that spell of no sex, contrary to some beliefs you can live... albeit frustrating, but its not a life threatening issue.
As far as dating while you are legally married ... I am still legally married, W left back in Nov13 and sure .. I thought about dating .. she had her OM "why not me" type of thing. I was still attempting to save the M so I held true for a long time. The D thing started rolling its wheels in my direction so a about a month ago I figured ... why not, I went out on a date with a girl I had been talking to for a couple weeks. She new my sitch, everything was out in the open .. not concealed.
We meet up, had a great time ... really did. That being said on the drive home I realized quickly, not what I want, not who I am, not who I want to be, most importantly I am no where near ready to open up and share myself emotionally. It just did not feel 'right' even though it was fun to go out and GAL. This girl asked me "Would you ever get married again?" I was not ready to even attempt an answer nor think about that question. I have been in a R with my W for 24 years, married 14. I am not sure how long it takes but I do know that for me, it was not fair to this girl I went out with (she was ready, looking to move on and into a serious R) ... I am not ready to just jump into another R when my M is still all be it on paper, legit and who knows what may come of it.
As far as dating and flirting pumping up an ego ... not so much. The ego and confidence I think stems from within .. just as we have found out that one can never make the WAS happy ... nor can an outside influence truly make us happy, that comes from within. Flirt and wink all ya want ... push comes to shove the confidence is not there nothing else matters. Date when you are ready .. not just to one up your WAS ... that R will not last. If revenge is truly your motivation I dont think it takes much to see that will not be setting a great foundation.
My opinion, at this time in the game, at our age (anything mid 30's and on) we all have some baggage. With what a LBS has gone through, serious baggage that must be dealt with or the next R when and if that happens is going to be set up to fail. A wounded bird can not just jump out of the nest ... heal, mend, regain confidence and then when its time, fly.
