TL;DR: Does having lots of hookups / casual sex / sleeping around "get it out of your system" at some point, or do people who engage in that always have the urge to look for more?
I'm going to try to keep this short, even if a longer post with more context might be useful at some point too. As you can guess, I don't understand the mindset people have that have frequent hookups / casual sex and don't have the most positive view on it: I'm convinced it can't be good for mental health and future committed relationships, whether that's because it conditions you to think the "grass is always greener", makes it less likely to work through uncomfortable situations, adds in apple-to-oranges comparison factors, or many other reasons.
Coincidentally though, my girlfriend has had A LOT of casual sex before meeting me (~with around 30 different people in the span of a year). (Again, I won't go into details as to the reasons for that – strict parents, stressful time, etc – in this post since this is supposed to be a simple question) This is her first serious relationship, and we've been together for 2 years now. It's also my first relationship, and she is my first partner in general. While I know a little bit about her past, and do have this morbid curiosity to know more, I try my best not to bring it up because I know that it's going to be uncomfortable for the both of us – she's even more conflict-avoiding than I am, and this topic already fucks with my head more than I would like it to anyway (again, different topic though. Maybe I'll create a separate post for it.)
In the very few short conversations we've had over time where this has come up, she's mentioned that she "got it out of her system" and is not interested in that anymore. Maybe her way of subtly showing commitment, given that we don't really talk about "serious" relationship topics since it makes her uncomfortable – which doesn't exactly make it easier for me, but anyway.
But I'm interested in how much this realistically actually applies? Clearly something like that will always have some impact on a relationship, whether it's her fear of (talking about) commitment or my discomfort/insecurity with this particular topic. For people that have also slept around a bunch, regardless of whether you are in a committed relationship now or not, what is the mindset like for you? Does that "need" disappear at some point? Or do you get bored with your partner at some point anyway, and just ignore the urge to look elsewhere?
Very different and more extreme thing, but I know that the rule of thumb for cheaters is that there is no such thing as getting it out of their system, and the likelihood of them cheating again is very high. Don't get me wrong – I have full certainty that my girlfriend wouldn't cheat on me, I know that she loves me. But does the urge to look for the next most exciting thing, or whatever the reason for sleeping around is, actually disappear, or is that just a way (lie) of softening the blow / reassurance?
I realize this might not have been the best way to formulate the question, since I didn't provide enough context to ask for advice for my concrete relationship, but also didn't keep it general enough to not introduce bias. But I would really appreciate some constructive comments nonetheless, if possible. Thanks!