I just want to offer a different perspective, although I'm not minimising what you're feeling, I think you might be BU without realising.
My first point is the usual corona one: that this isn't a normal situation and I really think we need to cut people some slack. There seem to be quite a lot of "my friends aren't doing enough" threads lately, and equally abundant "I'm overwhelmed and can't cope" threads. Maybe the friends that seem to not be doing enough are the same ones that are at or near breaking point?
My second point is that when groups are formed (even groups of two), people fall into roles. If you're usually the one to instigate conversation then that will continue through habit. That's become your role: you control the amount of contact. It doesn't mean your friend doesn't enjoy your conversation, it just means she's happy with the level of contact you have so she doesn't feel the need to instigate any additional contact, because you're already doing it. If you've stepped back, she might not have realised or she might just be sticking to her role: she's the one who replies. It sounds simplistic but it's really easy to get into these routines and people don't break them quickly.
The third point is from my own perspective: I reeeeeally dislike talking about my feelings. So if someone asks me I'll do a quick "I'm fine, how are you?" but I generally won't elaborate even if I'm exhausted/overwhelmed/my leg's falling off etc. I do appreciate that people ask but I don't like the conversation, so I generally won't ask others either. I will of course listen and try to help if they venture information but I don't like to pry. Obviously you know your friends but some people are just more private, and it could be possible that they see things similar to me.
I think in general as an adult if you want help you have to ask for it, which includes emotional support. You could say "I'm having a rough day and need to rant, do you have 5 minutes?" etc.
Obviously might be off base but just wanted to suggest alternative viewpoint. Sorry that was long.