Help! Need advice.

My friend and I typically talk on a weekly basis, sometimes multiple times per week, or we'll go maybe about 2 weeks of not being in contact when we are especially busy. If one of us reaches out in between by text or something, we'll get back to each other at least in the next day or two, even if it's just by text until we have time to talk. We both work and are understanding of each other's schedules, but we do talk a lot.

The last time we talked (at all) is when we went out to eat, and that was on Sept 18. I did not hear from her for 3 weeks, so I reached out with a quick text checking in with her to say hi. I called her a few days later, but nothing. I figured she was busy, but it didn't seem like her at all. There were a couple of other unsuccessful attempts. My last attempt was just a text two days ago Oct 14, and I said that I hope she's okay, that I don't want to bother her or keep calling, and that she can tell me if she is just needs space during this time. I asked if there is anything wrong and that I'd just like to hear from her (even if it's a text, just to hear from her).

I am not a clingy person. It's just that I trust my intuition when something is wrong, and this is unlike my friend. I do know that she is especially sensitive during this time, very stressed about different things, coping with being separated from her husband, who was verbally and physically abusive in the past. It has been ongoing though, and their relationship has been okay since being separated and co-parenting.

I also know that she had to call a hotline, where she had some suicidal thoughts only a week before we saw each other. She has a young daughter though, and she said that keeps her motivated and brings happiness. However, she has been coping with these issues for a while, and it's not part of her patterns to have zero contact for a month, even if someone reaches out.

I don't know what to think. The only other way of contacting her besides her cell is a P.O. Box address, that I hope she still has. Or, I can look up her workplace (if I can find it) and call asking for her, but that's a last resort.
My theories: A) She lost her phone contacts B) Some kind of emergency happened, God forbid, being in the hospital C) There's a misunderstanding between us, or something was taken out of context?? This would be unlikely, but like I said, she is in a vulnerable spot. She does have a personality where she reads into things a little too much. I'm in the dark though.

What should I do??? While reading this, what do you think would be more likely to happen? I know that nobody has answers, but I really need input. I want my friend back.