I can relate to what you are saying. I am a big "thanker" and, if I'm not careful, I can become a door mat too, meaning I have a long history of letting people walk all over me.
There are so many times throughout my life where someone would do or even say something nice to me/for me and I would feel like I owed them something as well. Although I don't blame my Mom for this, I do see where this was a learned behavior that I picked up from her. My Mom would always give things away, even get money out of her wallet as a way of saying a simple thank you. If I'm at the grocery and someone sees me struggling with getting something heavy into my cart and helps me, my first instict is to go over the top with thank yous, complimenting the person on something, anything.
I am a big card person. I send people cards just to let them know that I care about them, thank them for something nice they have done, words of encouragement when they may be going through a tough time . . . While I don't see anything wrong with this, I can go overboard as well if I don't "check myself."
As far as the apologizing, this is something that I still struggle with big time. I am getting better, but I know I still have a ways to go.
Regarding feeling obligated to answer everyone's replies to your posts, I personally don't think that's necessary but if it's something you feel strongly about, that's up to you.
In early Recovery, I think we all begin to see all kinds of character defects/quirks, whatever you want to call them. I think this is normal because for the first time in sometimes years, we aren't medicating ourselves and these things are all a lot more obvious to us.
God Bless,
Judy