How to talk to this person?

If anda can't tell, I'm not a very social person and I don't really get out much. I used to have a small lingkaran of friends and we kinda weeded out who we like and who we don't want to be around. This began a very awkward manga-like situation where i accidentally got a boyfriend and his ex girlfriend is hitting on me after she asked out my sister. And age differences and stuff.
BUT ANYWAY, there's this one girl I know, she's a lot like me but she has lebih ambition and she seems to be quite outgoing and populer but sometimes when I talk to her she gets so freaking deep talking about guys she used to go out with and her current boyfriend who lives on the other side of the state so they hardly ever get to meet up. Sometimes it's really light, we talk about anime, music, she's been giving me makeup/clothing advice, etc. But when she gets going on a topic she's passionate about(she wants to go to Japan, she's setting up a job with the owner of a local store, she wants to get in a foreign exchange program, she wants to be a cosplay artist, she's so freaking passionate about a movie she watches that i recommend to her it's almost hard to keep up with?) atau something lebih upsetting like her boyfriend, I just don't know how to respond. I basically just started talking to people like two years ago, I'm pretty much like Crona from Soul Eater, I have no idea how to deal with people and I'm not sure how to respond to things like this. If it was someone shy like my sister I'd just reassure them but this girl is like my idol and i don't know if i should like just listen and nod atau try and offer saran atau help atau if i should say something. IDK