Absolutely not. If David was sad to the point of removing songs from his album, don’t you think it would show on his face and in his behavior? David looks everything but sad, lately.
Also, I’m not even sure Someone else’s girl is about Gillian and the other new songs he played during his last tour didn’t seem to be about anyone in particular.
I don’t know why his album is delayed, it could be for many reasons, but I think it’s mostly because David doesn’t know how long it takes to make an album. He said so during an interview last year, he announced a date and said he actually had no idea how long it would take. It was he who said it would be released this spring, but last year, he said it would come out last fall.
So I just think we can’t trust him on that. That’s all.