AIO to be upset that my best friend didn't invite me to her birthday because of my difficult life situation?

Hello. I'll say right away that English isn't my native language, so I'm very sorry if there are any mistakes. Today I texted a close friend of mine, whom I've been friends with for at least five years, to find out how she was planning to celebrate her birthday and when I could come congratulate her. Her birthday is in a week, but I've asked this question before, and I've always received responses like "I don't know," "I don't want to talk about it," and "I'm really busy right now, ask later." Today, I received a reply saying she was going to visit her friend in another city that day, so we wouldn't be able to spend time together, nor would I have time to give her a gift. I was upset and said it offended me, since we usually celebrate such things together, and I know her friend well and we've spent time together before, so no one was stopping her from inviting me. It was also disappointing that, as it turned out, she'd already known this and just didn't want to tell me. And like a fool, I prepared a big surprise, spent a long time learning how to make a cake (I'm a terrible baker) to make sure everything turned out perfectly, and now I'm sitting here with all this not knowing what to do. My friend said that her friend also invited her under the pretext of a surprise, and when I said that I was also preparing something and wanted to be part of her plans, she said it didn't matter and she didn't want it. And that she shouldn't worry about anyone but herself that day. When I asked why she didn't even think to invite me, she replied that a year ago, she and her friend and I had a small fight, and it really upset her. I don't remember that day very well, but I do remember that we argued over something trivial, but afterward we made up and everything was fine. But I was the one who started the fight; I was unstable at the time, and something very difficult happened in my life that day, because of which my psyche failed. Let me clarify that I've been diagnosed with anxiety and depression. But I worked on myself after that, took medications, and spent a lot of time with a psychologist. I was deeply affected by that situation and didn't want it to happen again. But my friend said none of that mattered and simply devalued everything good that happened after that, focusing only on the bad moment that happened a year ago. She also mentioned, quite harshly, that my life was pretty shitty right now and that she didn't want to sacrifice her comfort for me. Yes, I was recently diagnosed with a severe chronic intestinal disease, and because of it, the doctors told me to stop taking all the heavy medications. Besides, my father drinks, and I often face abuse in the family. But damn, that doesn't mean I've gone backwards in my development; I'm holding up pretty well, despite everything. Is it really okay to be friends and spend time with someone only when they're doing well? And when things are bad, they're no longer a friend and you need to distance yourself from them? Besides, why didn't she talk to me about her concerns? We could have discussed it; we always had such a trusting relationship, I thought. Now I don't know. When I said that this situation was hurting me, she told me I had no right to talk about it, and I only made her angry by this conversation. That I was annoying her. Please tell me, should I really have said that this hurt me, and what should I do now? She doesn't respond to my messages anymore, she only reads them.