Didier,
boy did your post bring back some caretaking memories! I spent a few years in cognitive therapy after the experience. Went through guilt trips that I didn't do enough or what I did do, I could have done better. Business and relationships went in the toilet and I had NO control over my life. My psychologist freed me up a little when he told me that I wasn't responsible to DO everything - just insure that it got done. So I got help and some respite care to take at least part of my life back. I also went through the greiving process for my old, pre-caregiving life. It made more sense to me after I accepted that fact. There were times that I was really angry about the whole thing.

You need to take care of yourself. You won't be worth anything to anybody if you don't. Find some help, take a day or two off. Sometimes the local churches will have an eldercare ministry for providing respite care. A support group is a good place to vent and find others going through the same experience. You may find additional resources to help you out there as well.

If your dad is terminal the hospice programs provide respite services as well. I would have never gotten through the process without them.

I have lost both of my parents and it's hard not to see yourself there as well. My father died from non Hodgkins Lymphoma and my mother had a massive heart attack. It really sucked. I know exactly how you feel...