So don't seek out comparisons, and if your dude brings up the topic, tell him you're not interested in hearing it. Don't try to keep your boyfriend and your bud from associating because you're afraid they still have feelings for each other, and don't constantly seek reassurance that that's not the case.You and your friend are not in competition, except when you're actually playing Scrabble. Trust that your dude is with you because he likes you and you're awesome, not because he's biding his time until your friend takes him back.If you're gay, you will almost inevitably date a friend's ex at some point.Queer communities are often small and insular, and once you've found one, you tend to hold on to it for dear life.
Save it for your diary or for anyone who didn't date him. This can be extremely tempting if they ended on bad terms and you know you'll find a sympathetic ear.
They wholeheartedly believe that it's wrong, disrespectful, and if a friend did that to them, they'd never talk to that person again.