The concern here is that she has shown a pattern of ultimatums which is not healthy for a relationship. It's actually a red flag as it is controlling.

Forcing you to get rid of your dog is just going to breed resentment between you two.

Keeping him could possibly do the same.

You can keep your dog and just break up with her and still be a father to the baby.

If you go this route I'd suggest you consult a lawyer immediately and say nothing until after you have found a new place to live (unless you own the place).

If you do the doggy daycare route you need to have a good amount of money.

1yr is like $3120. That isn't including gas if you have to pay someone to take him to doggy day care.

That also isn't accounting for any vet bills you may incur if he is attacked or he attacks or if a dog gets sick and your dog also gets sick.