What I want to say is that even though they do their best it simply doesn't come out the way they would love to.

I think it goes back to how your parents were parented in their childhood. What I mean by that is they are likely to have picked up on the qualities that their parents had which they are now reflecting upon us.

If your grandparents are difficult to deal with, a part of their bad quality was unconsciously and unwantedly adopted by your parents when they were young. The same happens with us too.

And it becomes really difficult to get rid of that bad quality if you don't realize it soon enough as it slowly becomes a part of your personality. That's, I think, one of the main reasons why toxic parents are toxic in the first place.

Thank you for you kind words. Really helps to know that other people are sharing the same problem. I wish you the best :)