I [M/early 30s] am a single man just have an argument with my best friend for more than a decade[M/early 30s]. Now he is ignoring me and I feel devastated if it means losing practically my only friend in the country.

Some backgrounds: I am a man in his early thirties. For my whole life I have struggled with making friends and romantic relationships. After moving to a new country together with my best friend from university for career purposes, despite effort to keep in contact with my old friends, gradually most of my old friends started to drift apart. My relationships with my colleagues are cordial but not close. Regarding romantic relationships, I did not meet my first girlfriend until I was almost thirty. After who I thought was the love of my life dumped me, it took me a year and a few months more to gradually recover. Over that time I have taken up fulfilling hobbies again and started working out again, and doing things that make me gradually learn to enjoy life again. I recently recovered enough to start taking up online dating, and even have a couple of first dates upcoming in the next couple of weeks, hoping that one of them may turn out to be my future wife. I work in a high-stress long-work-hour career, and it is often difficult for me to try to have a life outside of it, but I do say I am trying my best.

The friend I just had a fight with had been here for me through everything since we were in our late teens. He was here when I struggled with being perpetually single, and when I was breaking down after the breakup. He was here when I struggled with my career stress. Now I know I certainly have of flaws, I don't claim to be a saint. During the low points in my life I can wallow so much in my problems, that I sometimes failed to notice that my best friend have problems he needs to deal with too. In contrast to me, my best friend is very sociable, and sometimes (especially due to our busy career schedules) he cannot make time for me because of his prior engagement with his family, other friends, and his significant other. Therefore, we mostly communicate over Facebook messenger. I must admit I sometimes get a bit annoyed that I am often left to fend for myself, but apart from a few incident I generally did not show that I am annoyed.

The argument in question occurred in the weekend. There was originally talks to hang out in the last weekend, but nothing definite yet. A few days before that, I messaged him, and he said "maybe", but needed to check after. A few more misunderstandings later, on the day of the meeting I had reserved the time for him, but he told me he wouldn't be free. I decided to point out the miscommunication and said that hope that we can communicate better in the future. When he claim he was being clear, in the heat of the moment I posted screenshot the parts of the conversation that I thought lead to the misunderstanding, and that if I have known earlier I would have made other plans. And then he started getting annoyed, and say I shouldn't have planned my entire life around his schedule. I said that "You are my only friend, of course I plan my schedule around you". He said that he feel so pressured to be my only friend, and that if he has to watch what he says around me then he feel so pressured, and he doesn't know how to respond to that. Halfway through the conversation I have already decided that he mattered to me more than arguing "who is right" and just started apologizing. But still, after a few angry rants he disappeared.

And since then he had not spoken to me again for days. I have tried to send messages after messages, trying to apologize for any perceived flaws that I have, in hopes that he will come back. After some "seen" messages that he didn't reply to, I think he might have checked the "ignore message" option on Facebook, because the rest of my messages are going unread. Having no where else to turn to, I have talked about this with a couple of university friends living overseas, who kind of drifted apart from each other over the years. They advised me to give the guy some space, give him a few more days or so, and that if this means the end of our friendship then that is life. I wanted to give him a call, but I know he doesn't like phone calls and rarely answers anyway. Additionally, I don't want him to feel I am pressuring or smothering him even more, and destroy any future prospect of repairing our friendship.

Maybe I sound like a whiny teenager when I am a grown man, but I feel like the one foundation and one constant in my life, the guy who I considered my non-blood-related brother, is leaving. Maybe I deserve to be alone, because after so many years I still haven't made anything more than casual friends since university, and because I put so much dependency on one person. But even if in the end I made it through life without my brother, even if I found a wife and have children of my own, or even a new close friend, I think it still won't be the same because my brother would not be here. While sometimes I think I will be fine, that hey I have a good career, I have fulfilling hobbies, and I have finally started to get back to dating in search of the love of my life. Sometimes I feel like my world had collapsed just when I have finally fixed everything, and I have trouble concentrating on work, or other areas that may improve and help me enjoy my life.

I am worried that even these couple of overseas friends I am confiding in about this will eventually get annoyed with my problems and leave, and I guess that is why I am exposing my vulnerabilities to strangers on the internet. I do not know where else to turn to. And there is not a moment when I don't wish that I haven't confronted him about that miscommunication. I want to ask my fellow Redditors, how can I repair my friendship with my best friend? Can this situation be salvageable when he seems so determined to ignore me? Should I give him space to cool off like others have suggested, or should I keep chasing him so that he won't decide that he actually like life without me better and leave permanently?

**TL;DR: I am a lonely man in his thirties, who might have lost my best and practically only friend. I need help in fixing this friendship.**

**Update: The friend had resumed contact and basically resumed talking without acknowledging the apologises, after staying away for almost a week. This incident, and the advice by you here, had really made me see my errors. It is a wake up call to change. Please see a more detailed update in my comment below. Thank you everyone for being helpful in this time of need.**