I got ghosted by my closest friend and I don't know what to do/feel.

I made some good friends during university and the friendships kinda fizzled out which was expected. Except this one friend that I still talked to after me dropping out. We had many shared interests and similar views on things, we talked about anything and everything. They have told me before that they considered me one of their best friends/favourite people, and I do the same. It was mindblowing how genuine our relationship was, I have never experienced anything like it, I thought we truly understand each other. We always talked about our thoughts and feelings in detail, just so there's no misunderstandings.

Early this year we went to a big event near their town, and I stayed at their house for 2 days (not my first time there). We both enjoyed the time when we hung out together. After I went back home we continued our normal communications, which is just texting and sending shitposts occasionally. And after a few weeks they stopped talking to me completely. On all platforms. I was worried at first, and asked their sibling (that I don't know very well) about their safety. The sibling told me my friend is physically safe but feels very stressed at work, which is understandable. I know my friend has a history of going offline for a period of time, I've experienced it and they always come back so I didn't mind. I didn't rush anything, I didn't spam text, I only sent a few words of support and some memes, and pics of my cats.

And then a few months later BOOM. I saw them updating their socials. New pfps, new posts about recent night outs and clubbing with friends and daily life stuff. It hit me like a truck. I'm not bitter that they're having fun and enjoying life. It's just the fact that they wouldn't even read my messages. I don't know what to make of this. I'm not banned from any of their socials, I could see and like all their posts, and I did. What I did not is comment on them, because I'm not the type to confront, and I don't want to make things awkward and break what little bond we have left. There were no signs, there were no reasons, nothing bad happened between us.

I've told some friends about this whole debacle and they all told me the same thing, "oh friendships are like that sometimes, it just fades out with time" But they don't get it, this is a sudden thing without any signs. I got ghosted out of the blue. I have plenty of past friendships that have faded out naturally and I take them well. This is different. This is new. And I'm confused, I'm torn, I'm a little hurt. It's been troubling me more than I'd like to admit.

Anyway even if you don't comment, thanks for reading. Typing all this out has definitely helped a little bit.