As difficult as it is, it's best to leave friends and family out of it.
You and your H agreed to transparency (RE: dating) when the trial separation started, correct? Has he told you about the online dating profile? If not then I would say he has not held up his end of the deal w/transparency and you have to make a decision on how you will handle that.
This is just my opinion but this is in large part while "controlled separations" or "trial separations" simply don't work. The WAS views it as another step towards a divorce while the LBS feels it could be a stepping stone towards a reconciliation.
Other than providing financial support and doing fatherly duties your H has been living the single life. Would you say that is a fair assessment?
I wouldn't call it cake eating as you H doesn't seem to be treating you like a W when it suits him. He is very much (IMO) in full WAS spouse and is waiting for you to get on board.
