The huge thing my OM friendship is giving me is some strength and more understanding of H. I know that is a bit demented.
No, it's not demented - it makes perfect sense actually.
The admiration of another man rescues your self esteem and helps you detach. And seeing how easy it can be to slip into another R, makes you understand a little better how H slipped into his affair.
But yes, it's dangerous, because you might get your feelings involved and then not be able to go back to your marriage even if H wants to try. Or your H could come back and you could end up hurting OM.
That's why I sometimes advise people in your position to create the APPEARANCE of dating (going out all dressed up, being mysterious about where you're going, buying yourself flowers and leaving them around as if someone sent them)- without really dating - so as to provoke the WAS into feeling exactly what your H is feeling now, but with the ability to deny in the future ever being with another person.
Unfair though it is, if you were to sleep with OM and then reunite with your H, odds are that he would continue to hold that over your head and resent you for it.