We've all backslid and all you can do is learn from it so it hopefully doesn't happen again and try not to beat yourself up. Just get back on the DB horse.
I was also struggling with Christmas gifts but decided to get her a couple things from kids and nothing addressed from me. My reasoning is if she doesn't get me anything then it's not awkward and if she does then I'm acting "as if" I've moved on. Not sure if it's the correct thing to do but I'm done stressing about it so I feel ok about it.
Personality is who the world sees, character is who you are
