I never feel guilty.
Raised 2 daughters,1 son, and 2 grandsons and feel like I'm still raising them.
Have pretty much raised my 4 YO grandson since birth.
Still have to help kids financially due to the wonderful shape of the economy.
Have never told my wife she can't do something she wanted to do with the girls. Weekend trips, long trips, anything. I've actually allowed her to go, as I banked time for myself. Over the years I've built up a lot of "me" time. Even stayed home and worked/kept kids while she did her trips.
Do I feel guilty? NOPE..... and she understands.
If I have the money, I'll buy whatever I want. Don't have to talk it over with her.
If I don't have the money, I just don't think about buying things.
But Guilt never enters the picture.