I don't think at all you sound like an abusive parent. It sounds like you have done everything you can to look after your children and grandchildren. Living with mental illness is never easy and it can be extremely hard to look after other people while you are also struggling. I know that can be really hard for children to understand but it sounds like you did the best that you could.

It sounds like you are doing well with your grandchildren - ultimately it is the time you spend with them that they will remember in the future. I don't remember so much the gifts my grandparents bought me but the special times we spent together - when we went camping, slept-over etc. For my other grandparents who live out of state I have some very cherished possessions but for my local grandparents I would never replace the time we spent together with any kinds of gifts.

Can you talk to your daughter about what she thinks you are doing wrong? From everything you have posted here it seems you are doing all you can to be a good grandparent now that you are in a space where you can spoil the kids a bit (and hey, isn't that what grandparents are for? )