How am I going to re-bound?

How am I going to re-bound all the lost relationships with friends?

It sounds like I’m in despair where there is not a single friend that can hang out when I need in these days.
Briefly speaking, since this February up till now, I lost three relationships of friends. If I have to classify these relationships by degree of friendship of my justice, one of them was the one of best friends and second one was just reunited from more than five years of gap and lastly, the third one was just met through school.
I was not believed in that I have thousands of friends which can be bragged about but I was pretty confident that I have been good in relationships with my friends that I have so far.
The first friend case in among the lost relationships, she was getting divorced when she just had newly wed not so long ago and so started seeing things all twisted. Ever since then, argument between she and I frequently came and grown and at last, I became the person who can not understand a friend who is in a difficult situation. From my perspective, of course, tried to say things out as rational as possible but that became too straightforward as a cold person who doesn’t consider its friend’s situation.
The second friend case, we were not in a great relationship before but just met again because I came here to New York last year and she was here in NY already. In general, back in where we were at high schooler, we wouldn’t acknowledge a friendship if we do not like the way of each other’s thinking. So when I met her this time, I was hallucinated that may be we are matured enough to acknowledge each other’s differences. And also, we were neither an enemy nor a stranger so there were no obstacles seeing each other again. Great time, fun at the beginning, but bitter time has come after all. Often we had to face different views in opinions. Now it’s gotten so badly so we both do not even try to convince one another because of huge gap between us.
The last one, simple. She went out with a guy I just used to date not so long ago even though she has a boyfriend. So didn’t even bother. I closed the relationship.
All of that, I have thought millions of times to find out where problem came on these issues and how I’m going to wisely get out of these of not so pleasurable situation.
It suddenly occurred to me that if I’m not having a difficulty to live without them, why would I bother? It’s not something that I want to make enemies all the time. Unlike when I was younger, I just don’t have energy to reconcile or try to convince or compromise. In addition, if that’s going to be not a best solution that we are seeing without affectionate we used to have, what’s the matter? Seeing them but it’s like idling and spinning round outside of something real.
Is it may be a management problem? Also, in a friendship, do we have to play a game not to be sick of each other? Do we have to have our own personal spaces on a regular basis? It’s like watering flower like, giving them a moderate amount of water and nutrition and saying things pretty to make it flourish?
Has friendship in these days changed in need of management? And can we call that friendship? Somehow, that sounds so pathetic but may be yes, I may need some type of management on this.
Anyone could help me finding out what’s a smart way to isolate the problems in relationship management?