Should I still get my friend a present when I feel really resentful about our friendship

I’m not sure if I should get my friend a birthday present because I feel really conflicted about our friendship at the moment.
We used to be really close a few years ago. She was there for me a lot, including helping me with job applications, and I always felt like I could rely on her. But over the past year or more, she has increasingly started ghosting me. She can disappear for weeks or even months and won’t reply to my messages, even when I’m going through a really difficult time myself.
She says it’s because of her mental health and that sometimes she genuinely can’t bring herself to respond. I do understand that mental health can make communication difficult, and I don’t want to be insensitive to that. But she’s often still active on social media and posts on her stories quite a lot during these periods. I know posting on social media and having the capacity to reply aren’t necessarily the same thing, but after being ignored for months and months…
She also lives about two hours away from me. I’ve told her I’d really like us to make more of an effort to visit each other, but she only came to visit after about two years, and that was for my birthday.
She has given me a few gifts over the years, including when I achieved certain things, which I genuinely appreciated. So I feel like I should get her something too, partly because I want to reciprocate.
The thing is, I don’t have many friends, and I genuinely would like this friendship to last. I wouldnt say I care about her, I’m not even sure I feel I’m holding on it out of convenience, the past and the years. But I’m also finding myself really resentful about how one-sided things have become.
Part of me feels like if I just keep buying her presents and putting in effort when she disappears for months, I’ll feel like a walkover — like I’m accepting this treatment and letting her get away with it.