Amazing story! You have an admirable stamina and patience to learn Swedish, it seems - very impressive! And I stand by my earlier statement; I looked through some of your posts written in Swedish (just out of curiosity) and it can easily pass as written by any native Swede.
I understand of course that it is easier in writing, when you have the time and resources to verify that everything is correct before posting it. But still, very impressive! Grammatically there aren't many errors, only detail I could notice though is that maybe some phrases/expressions here and there are a bit complicated/long. But mastering that is something I guess you can only learn by time and experience (such as being raised with the language for example).
If I look at a lot of people here in Sweden, most of them younger (I should add - I'm in my mid-20's), there are far more errors and mistakes in their writing than in yours. I've always been good with languages in school (not that I have found it very interesting, I guess I just happen to be good at it), and I also studied a year at the university here. There I found very few who could actually write a really decent text without a shitload of errors and mistakes. It surprised me, as I don't understand how the knowledge of one's own native language can be so low, and seem to have deteriorated so much just over these past few years. I felt it was honestly quite emabarrassing to see people master their own language so poorly in such an educated place as the university...
Anyway, my rant about my fellow Swedes and their poor language skills is over (I suspect my grammar nazism won't be, though)!
Just keep practicing and speaking (when you get the chance) and I'm sure you'll master your Swedish gallantly!