Dear Sparky,
The universe is huge, and expresses endlessly. What we call "our lives" is also the universe unfolding. Things are as they are. Carry no guilt or remorse fore what you have done or did not do. Or what others have done, or have not done. It is as it is. The universe unfolding.
Be silently present in the moment, and do not abide too much or too long in the drama, judgments and chatter of the mind. Be kind to yourself and feel what it is to be alive, breathing, and just silently be-ing.
If it becomes too painful, then that is natures way of saying it's time to change. Your mother may have to be placed in a home. Again, you have done the best you can, and the universe unfolds. Not so much because of our efforts, as for harmony in a hugeness we are mostly unaware of. It is as it is. Be at peace with yourself. Be kind to yourself. You are always doing the best that you can. If you could have done something different you would have. Same goes for your dear old mother.
j