Welcome to the boards.
I am really sorry about the situation with your wife. I think you need to take some time and take care of you right now. Are you still seeing a therapist?
If not, I would strongly advise talking to your doctor and/or going back into therapy. You need to work through the reasons behind your suicide attempts so that they don't happen again. Your life is precious, it just doesn't seem that way these days.
In the meantime, you've found a great group of caring people. Please let us know how you're doing and we'll be here for you as much as possible.
Mary Alice