As a dyslectic person i always struggle with grammar and spelling. Back in school (Swiss German) i could not figure out if there should be(e)?; a v or a f, an extra h in "ka(h)m"; and on and on and on...
The positioning of letters did not match on paper the way i had them in my mind. Lucky me, one day spell check was invented and i finally can write letters (still not perfect) but at least people understand the basic concept.
After reading the text beside my theory has bin proven correct, it's not that important at all, and more important, you communicate with people and try to learn new languages even there are plenty of mistakes (how else you learn if not with mistakes).
Don't get me wrong, this is no excuse, not to improve spelling and grammar :)