Instead of talking at each other about the non-business-related contact, talk to each other about your concerns about marriage. Listen a lot, too.

There has been, for some reason (or more likely an unfortunate accumulation of reasons) a trend over the past several decades for parents to do the work of parenting in the isolation of their own homes - and not only that, this trend has overlapped with the other trend of much deeper parent involvement in raising kids. That you also represent trend No. 3, more people raising kids solo, has only exacerbated a close-to-no-win situation.

Bodies and minds need breaks or the work suffers, this has been proven and reproven to the point where we don't even need to post links to support it.

If the guests want to wrest the check away from the host, because the host is also the guest of honor, then the guest who volunteers has to cover the whole thing. A guest can't volunteer -all- of the guests to pay for the host/honoree.

Plan your own vacations when you want to, and plan a suitable combined vacation with this other family when you want to. If they freak out at your planning your own vacations as you see fit, then let them. Bowing to unreasonable demands because someone will make you pay emotionally if you don't is not a healthy option.

I believe in innocence until there's proof of guilt and all that.

Awkwardness is when there's a risk of a perception gap between what you mean and what you appear to mean.