<human>: Give me the gist of the text in a nutshell

I usually operate with a "don't ask, don't tell" policy about the past when dating someone and it's starting to get serious. If they ask me explicitly, I don't mind talking about it, but I won't be the one to bring it up. Not that I have anything to hide, I've just always thought that the past is past, it's not relevant today, and if anything talking about ex-lovers would only bring up possible jealous feelings or other non-useful or negative emotions.

However, lately I've been feeling like maybe if you want to be with someone long term, you should know something about their past because it COULD be relevant in the present. E.g. they dated someone for 3 years and just broke up a month ago (maybe I am a rebound??), or their last relationship ended because they were cheated on (maybe they have trust issues?). 

I'm sure I can do without intimate sexual history but do you guys think the dating/relationship side is worth discussing... or best left in the past?
<bot>: Should you eventually ask someone you're dating anything about their prior relationships or just leave all of the past in the past?