I know I am jumping in here mid-stream....but I second what Cat has told you...basically you are playing with fire...you kissed once...okay 3 times...next time will be easier...it isn't out of the way it is square in front of you...talking about the possibility of seeing how things would go "if" your M doesn't work out...well...again, not a good idea because it is funny how all of sudden things can seem not to be working out...I know, I went through that a few times during the time my H was gone...I did get involved with a man although there was no kissing or other intimacy except for a hug and a back rub...but when H and I finally did get back together I felt incredibly guilty about my behavior with a man especially when I KNEW I loved my H...it didn't matter that he had an A...and a PA at that...it didn't matter that he couldn't tell me he loved me....not even for nearly a year after he returned...
Yes it does take time for the WAS to get over the OP if there was one...but given time and patience it does work out...
Sorry for butting in but I do hope things work out for you...piecing is incredibly hard...and you will question yourself often...but if you can make it through with your spouse you will know it was all for a good reason that you endured...