Well as I said in those 5 weeks we did what other couples do in 3 years. I don' think you can always judge a relationship's nature by its duration. It wasn't a "so-called relationship". He called me his girlfriend, made plans, talked about wedding and kids and took me to his parent's place, to his best friend's wedding, he asked me to move in, he talked about me to his friends and family.
I don't think it's odd to be emotionally that invested when you love someone and on top of that know that they need help.

But where I agree with you is what kind of human being writes a nice email asking how I am and suddenly goes silent without any explanation. My answer to him was friendly and relaxed. I don't understand why it happened so out of the blue.

He still owes me the money for the flight. In the past he always insisted on paying his debts. So that's odd too. When I owe money to someone I want to break up with I pay immediately to be rid of my obligations or at least write that I'll pay at a specific date.

I don't get his sudden shyness. He tried several times to end it. We talked and then he changed his mind, telling me (like it was a bad thing) that I always changed his perspective on things and convinced him he wanted to stay with me. As if I was brainwashing him!
Every time he said we had no future or that our 5 weeks were like 3 years so we had our time together or when would I have enough, he backpedaled saying he loved me, wanted to be with me...

But his plans with me became more and more vague. He didn't talk to his friends and family about me anymore. When I told him, he said that he needed time to settle in and to figure things out. I told him that if he wanted a breakup, it was better to do it now, that I didn't want to be blindsided when he was home, that he would quickly forget me anyway, he told me that he didn't understand why I thought that he wanted to get rid of me, that it was the opposite: he was trying to keep me from leaving him.
But when I mentioned that at one point he said we should stay friends, he didn't say "I didn't mean that".

Later that night after I mentioned his drinking, he said I was deciding everything, controlling him, and stormed out to get wasted (typical alcoholic behavior).
That made him realize that he needed help (that's why I didn't prevent him from going, I was hoping for that wake-up call) and that's why I helped him with the plane ticket. He left everything behind.

After 3 days I asked how he was by email. I told him I cared and asked him if our relationship was over. He answered: "Sorry, did'nt read any of it, i ll read it properly later. I have been drinking constantly since i left you, drinking now". He never reacted to that letter after reading it "properly" so I still don't know if "when I left you" meant "when I stormed out" or meant "when I dumped you"
Later he wrote: "Thanks for the offer to help, even after everything you are still kind to me. I appreciate it. Sorry for everything that went wrong, "You're very kind, i don't deserve it.", and "I am close to tears. I can't thank you enough.".

When I didn't get the email he wrote early the next morning confirming that he made it safely because it was delayed (he missed other flights before because of drinking), I wrote: "if you care, let me know you made it safely, so I don't worry", he wrote "of course I care, I miss you. I'll contact you again tomorrow from a cybercafe" He had borrowed his sister's tablet to write that.
He contacted me but only 2 days later (no cybercafe, he found an old computer). He was cheerful but told me he had been very busy and that the keyboard didn't work properly. I took this as a way of saying: I don't want to write so often.

How can I ever trust anyone after this?
Why can't he be honest and say like he did so many times before "we have no future, I'm sorry" and then stop writing. This time I made it easy. Why is it suddenly so hard to say it when we are apart and I can't "convince" him otherwise.
He was not shy to be brutal before.

Yes I have many questions but isn't that natural? Wouldn't any woman in my situation?
Yes I care a lot but feelings can be intense quickly when you thought you found your match.

How can I take the power back without even hearing that it's over. I have no idea what's going on. I really want only one answer: is it over. He can keep the justifications for himself.

If he hadn't an alcohol problem, I would have given up already, trust me.
But here I don't know what is dictated by beer and what reflects his true wishes.
He may be depressed and lost.
If I need to give him time, I need to know.