These are some very serious issues, Eddie.  Both you and Karin have been through a lot.  And made some mistakes.  The bad part is I don't know how you'll recover from them.  Miscarriage, family abuse, external relationships, all seriously threaten a relationship.

The good part is we all grow up.  Maybe more so in our late twenties and thirties than in our teens.  There is so much to learn about commitment, love, and relationships that you can't even start to experience until you have become an adult yourself.

I suggest you write Karin a letter.  You already have a good start with this letter - it shows how deeply you are feeling the stress and conflict of your marriage.  Let her know how important she is to you - and what you would love your relationship to feel like.  I can tell you love her deeply and expect that you will for the rest of your lives.  Just keep telling her that.

Karin may have some issues that are more individual than part of your relationship.  Ask her how you can be  a part of her dealing with them and also how you can support her while she deals with them herself.  I bet you will need a professional to sort them out.

Best of luck.  I sense how committed you are, and that bodes well for your relationship.But commitment isn't just a feeling, its acting in a way that will continue to show that your relationship is a priority.