That's true
i currently work with 3 men who are in the their mid 50s (i'm a 21 year old female!) I can't really relate to them but i still try and have a laugh and a joke. Maybe if you initiate conversations they'd probably be more than willing to talk about things other than children and mortgages. There must be some things in common - funny stories, films , music etc.
You should thank yourself lucky they only talk about kids and mortgages! i have to listen to how they're suffering from depression, debt, personal medical problems which i really don't want to know about, loss of sex life etc
!
Maybe stick it out for a bit longer, things might improve and it would be a shame if you left impulsively and then regret it...and if things don't get better at least you can say you gave it your best shot!
Best of luck