Umm ... if I'm with a current boyfriend I don't bring up my exes except if it's in a very casual friends context (I am friends with a lot of exes because I tend to believe that if you're with someone you are with them for a reason and you don't need to lose the whole relationship after a romantic breakup).

But I would never make comparisons. That is disrespectful.

Going on about 'Oh my ex did this', no matter how you mean it, can be perceived in crap ways. I just think it's the wrong way to reference past relationships.

Nothing wrong with telling each other about your former partners, but IMO it needs to be within a set context, not throwing random comments around.

It always unsettles the other person, no matter how you mean it.

Just IMO.