Do I tell my ex-boyfriend's new girlfriend that he is a pathological liar and a habitual cheater?

I was with my ex for a long time - 8 years - before I found out he had been molested as a child and had no ability to maintain ual boundaries with people who showed ual interest in him. I found out - after we got married! - that he had over a half dozen affairs with various women while we were together. Thankfully I was able to get the marriage annulled. I know he has not told his new girlfriend of his problem with other women and I know that he has still not sought therapy for his mental illness. Do I warn the new girlfriend? Or is it impossible to not come off as the jealous jaded ex? Do I just leave her to fend for herself? I should also say that he had with both random women and with close friends of ours and never felt enough remorse to tell me about it.