I made her the centre of my world and I seemed to have been penalised for it!
No, you were not. What happens though, is that people change over time, that's a fact. Also, going through this and when a spouse decides to no longer be with us, things that may have been endearing to them at one time no longer are and become a nuisance. It is what it is. Trying to figure it out will lead you down some dark paths that you do not want to go...I know, I've been there.
There are moments in this life when you are so confident in the rightness of your actions, that not even for a second do you consider the option that you might be wrong.