I obviously don't have any "sources close to the band" but this seems like just another spin of the old "Dave is tired of touring and wants to see his grandchildren grow up" rumour.
I don't doubt that he misses them while on tour, but it's not like he's away for 10 months a year or so. Sounds like someone has, again, just put too much emphasis on some random quote by Dave about the challenges of touring, as fun as it also is. I guess so, anyway.
Dave's stage presence was full of radiant joy (even in Dave standards!) last year and the band wouldn't be touring like this if they, Dave included, didn't want them to.
Sure, he won't do it forever and this might be their last tour, but all these "Dave reportedly unhappy with this and that" news are, in my honest opinion, milked to death already.