I think it is great that you are dating. I was just busting you because it sounds like you are falling quickly for the professor. I strongly agree with the others that if you want to pursue her or OW and you believe that your M is over then take the action to ensure that your M is over and file.
Until the D is finalized go ahead and date, but date OW as well and take it slooooooow. You don't want to be 30 and D'd twice. Unfortunately, I have a friend who 32 and D'd 3x.
