@Lochnessgiraffe
Nearly 18 years.
I'm crap at making friends and it seems to annoy him so I don't bother.
He doesn't have any friends either
No, no. It's not that you are 'crap' at making friends it's that he doesn't want you to have friends so he makes it unpleasant for you.
He's purposely isolating you from sources of support. From people who would tell you to leave him. This is probably why he doesn't want you having dinners with coworkers, he's terrified you'll make friends.
Another dog???? This is intentional to tie you to the house. Would you or the DC want to leave the dog(s) behind? No? So how much harder will it be to find a new home for you, DC, and THREE dogs? This is along the same lines as an abuser who talks their victim into a 'marriage saving' baby or intentionally gets his victim pregnant.
So, we now have THREE major red flags:
1-Trying to isolate you financially by belittling your job and making things difficult for you in your duties.
2- Trying to isolate you socially by making it difficult for you to make friends.
3-Trying to bog you down with responsibilities so leaving is a 'hardship'.
You really, really need to take a look at the totality of your marriage. If I were you I'd seriously be looking for my way out.