Why does caregiving feel like a burden?

Oh it is and more and more as time goes on. What I hate is how detrimental it is to one's health.

Do you mean caring for a loved one? If so, I would have to agree. Been taking care of Mom for close to 4 years, 24/7 the last 2 1/2. It is hard on everyone in my family too. It's never ending and even if you do get a way for a few hours, the thought of having to go back is always in your head.
Although I believe it is a good thing to be there for a parent in the end, I also feel that it's a horrible toll on your life and health. It's not an easy thing to do and we all have to make our own decisions as to how much we can handle.