My best friend stopped talking to me

My best friend stopped talking to me and I have no idea why. We’ve been friends since I was 11 or 12, shared everything there was to share, supported each other through all the teenage drama, college, marriage etc etc etc.

We talked every day, sometimes every other day, sometimes like once a week. Then one day I text her and she says “I have a headache, can’t talk, will text you tomorrow”. Okay, sure, get better. Tomorrow comes and there’s no text. Is she okay? Yes she is, “she just has a lot of work”. Alright, fine, happens, sure, will talk later.

In a week or so I texted again to ask if she’s fine or maybe needs help and the ignoring started. She read my texts but didn’t respond.

I joked, sent memes, asked what’s wrong, said I’m sorry for whatever it was. No response and I have no fucking idea why.

Later I asked her boyfriend if everyone is healthy in the family, because that’s the most important thing. They are fine he says.

I’m not texting anymore, she clearly doesn’t want me, but my heart is broken and I don’t even know if it’s my fault and how I can fix it.