The most common problems in a relationship is being emotionally wounded by those who hurt us by their comments that may sometimes seem intentional.
Some relationships, when complacency sets in, harbours unintentional hurt, such as bringing up issues from the past that aren’t relevant to what's going on.
Emotional baggage may usually be the reason why we may sometimes unintentionally hurt someone. However, if we make ourselves consciously aware of issues in our past, we can give ourselves the opportunity to work through and change how we relate to those we have in our lives.
Changing our attitude, if we are presented with these kind of problems, should allow us to deal with people and our issues better, so that none of what is said becomes intentional.
I've had people do this to me, especially my mother believe it or not.
My mother isn't an awful person but I wasn't her favorite and I really don't think she new she was doing this to me. I felt horrible at the time and just thought she hated me, but I was a young teenager and misunderstood everything that was said to me.
I try to be nice and if I ever say things like that to someone, I'm not intentionally doing it and I really don't until much later that I do these things, then when I think about it, I get all upset because I did it and didn't realise I had.
I think that until we make a conscious connection we probably won't know we are doing it as you say. It's only when we replay the outcome in our heads that we know we have.
I think like your mother I lot of us will behave in the same way. It's just a shame she doesn't realise how she behaves with you. I know you know she isn't an awful person, but just think how much better your relationship would be if she didn't behave in this way and how much better you would feel about her.