I(F23) find it hard to comfort my girlfriend(F21) when she’s upset

r/

My girlfriend and I are currently LDR, but this has been an issue long since before this. We’re about 6 years into the relationship, but whenever she gets upset, she doesn’t really tell me. She just acts a lil distant and not eager to talk. When this happens, I get a bit awkward too and I would try to talk about random stuff to get her to open up a little? But she would just give short replies and stay quiet afterwards. My problem here is that I want to comfort her, I want to talk about her problems, but I just don’t know how to start it? Like what do I say? If I ask her “you feeling okay?” she would just nod and say yeah with no explanation. I’m not sure if I should pry more into it when that happens? What if that makes her feel worse?

Usually how this issue “resolves” is, a day or two will pass and she’ll feel better, and we would talk like normal but I can tell she kinda holds a grudge towards me? I have tried to bring it up during this stage but she would say stuff like “isn’t it too late now to start caring?” and that shuts me up. I don’t know what to say to that. I’m not a very confrontational person and I have a hard time trying to put my thoughts into words. So even if I manage to start a discussion about this, I have trouble just trying to continue it. I have this fear that whatever I say at this point, it’s just gonna make her feel worse.

So I just want advice, how do I start being more assertive to start conversations with my girlfriend about her feelings and how to actually provide proper comfort for her during these times?

TL;DR I have trouble trying to find the right words to comfort my girlfriend when she’s upset