Advice for how to be respectful of my gf

Hi there, I know this is a subreddit primarily for women to talk with each other and I understand if I'm not exactly welcome here but I just wanted to talk about how to handle a situation with my gf if that’s ok.

Ok, so my (18M) gf (17F) doesn’t like to talk about her feelings, even when I can tell she’s upset or in a bad mood. I understand that she gets mood swings a lot and ofc I understand that, that's not her fault will never be something that I hold against her but it gets tricky for me when she doesn’t want to talk about serious stuff as she puts it since I'm the kind of person who likes to fix problems and I want to be there to support her and make up for my mistakes if I've done something wrong. I'm just wondering how I take care of her and support her in those situations without being overbearing or crossing her boundaries. Any advice is much appreciated 💖