"I love him, that is why he is my husband."
Translation:Kocham go, dlatego jest moim mężem.
Ehm... maybe if someone claimed that you loved John, your neighbour, and you were saying that that's absolutely not true; you love George - your husband, and that's exactly why you married him. Probably while pointing at George. So it's technically correct, but gives a strong emphasis for which there's rarely any need.
The second sentence changes the subject. It needs to be "dlatego on jest moim mezem", doesn't it? Is it really possible to skip the second subject? As I understand it, if you don't specify the subject then it is implicitly the subject from the main sentence, i.e. "ja" in this case.
You just mentioned the subject of the second clause by using "him", so logically it's the same person. Using "on" is quite redundant here.
I really am having a difficult time determining what version of my this is. It has been over my head this whole time.
Forget the beginning of the sentence, you can just focus on "He is my husband". Such a sentence takes Instrumental. So "moim" is Instrumental, and of course masculine singular to match "husband".
Well, the sentence is surely correct, I'm just not sure if it says the same thing. In the original sentence, the reason for which he is my husband (the reason for which I married him) is that I love him. In your sentence, it kinda sounds as if 'me loving him' automatically made him my husband. But I also love my parents and my children and my siblings...
So basically "X, więc Y" implies that Y is caused by X, like "X, therefore Y"?