friends for now? or friends for real?

I don't understand people and friendships today.
In the past two months I've had two people, both I've considered best friends, disappear on me. The first was involved in a month long teaching intensive which required her to be in class 9-5 and homework afterwards. I understand this and the need to prioritize and study. But this same person called me a week into it having anxiety and panic attacks, saying she was going to quit and I had to convince her to stick with it. Naturally, throughout the month I was calling to check up on her with no response. Not even a text . WTF. When the program ended she finally came back into the picture and blamed it on , you know me, I need to focus. Thats unacceptable. I'm your friend. Your BEST friend. You don't just disappear. Especially if I'm calling to check up on you to make sure you're not continuing these attacks, you most definitely take the 30 seconds it takes to send that text message. She apologized.

The second disappeared after my birthday and blamed it on being busy. Then his father being sick. Then on working on his writing. I obviously called his bullshit and after some 'I know you better than this' he finally broke down and told me. Apparently seeing me with another guy hit him hard. Now, this guy and I had dated in the past. Its been a long long time since we've been together. I didn't want to be friends after we ended but he insisted. So its been over a year and we've been the talking all the time sort of friends. He's been well aware that I've dated people.
The worst part is he blamed me for being inconsiderate and 'making out' with the guy in front of him. WHAT?!?! excuse me? This is after I received word that he was hitting on some friends of mine which at this point I overlooked. I was shocked. I told him that I can't apologize for something that I don't remember happening. It also sucks that I didn't want to be friends after we ended our dating run, gave in, and now that I've moved on I'm losing a friend bc of it? And rather than not responding to my calls and texts, why didn't he talk to me about it? I'm pretty understanding.
It makes me think he had ill intentions all along.
He later told me that it was him and not me and that bc he was upset, he realized he needed to step away.
I told him to take all the time he needed.

So, beyond ALL of this, when did friends stop talking to each other?
Especially if there are issues. Why can't we communicate anymore?
Maybe I just value my relationships more than the average person these days.
Sometimes I think family truly are the only people you can count on.