Listen here smartass, I know a lot of people can console this good fella over here as much as they want but I genuinely care for his success. I know what it feels like, I've been making near to nothing ever since I left Iran for America. You think it's easy to be happy? You think the guilt doesn't gnaw at this man?
Life is shitty, deal with it. At least if he looks for opportunities to grow in a career path, he'll have a story to tell on his deathbed instead of feeling sorry for himself like so many of us do. I don't think you know what it's like to be a loser and know it too, it doesn't help knowing there are other loser, you want solutions.
OP, I think you want to know how to get out. Well the fact is, even I'm not in any place I want to be either. I know you're probably still mourning your loss but I think first you have to come to terms with the fact that that the drugs and lies were how you mourned her. It's over and you have to move on. I'm sure that you also mourn the time you lost wasting your life over girls, parties and alcohol and maybe you wish that something could make the lies and laziness go away but nothing will. I think you know that.
What can you do now? You said you liked Media Management. Thats your way out. Like I said, there are a few options in this world that will make it easier to look back and scoff as this as just another phase. One of those options is, of course, IT. Especially in Germany. I suggest you look(like I said) for an many options to get into that sector(IT Media) as much as possible, go out and talk to professors and try and find internships that make you seem hireable. You said you were good with people and your High School grades were excellent, you must be able to intuit what choices you must make to climb the rungs of that career path and secure a place for your own children so that they don't have to go through what you did.
Even though we're half a world apart, I genuinely want to see you succeed, my friend.