No, you are not a wimp. You're a real man and should be proud of how you're handled this situation. Most other men would've done a lot more at this point...and would've gotten into a lot of trouble.
I agree, carry the recorder ALL THE TIME and tape everything. Its clear the anti depressants are not working and she has a worse mental condition than depression. She needs help and the only way she'll get that is if she's arrested - they will give her a psych evaluation.
If she or any of her family members hits you, call the police and file charges, no doubt.
Try to get some proof of her threats, even a few... also jot down some witnesses who may have heard her say those things as well. As soon as you get some proof, MOVE OUT and file for divorce immediately stating her unstable mental condition.
Be safe....