I just wanted to say, I couldn't imagine life without my dogs. They bring alot of joy. Perhaps instead of banning a dog from your home, you and your boyfriend should sit down and outline all of the responsibility of dog ownership (for both of you, if he has a dog, so do you). Figure out who will walk, feed and play with the dog and when. Never let the dog out unsupervised, always set your dog up to succeed. Having a well trained dog is very rewarding, but it requires constant work. You can't just leave a dog to its own devices (so to speak) like you can a cat or chicken. They need interaction and they need you to teach them how you expect them to behave.
Good luck, I hope you 2 can come to an agreement.
And by the way, growing up our family dog was a teacup Poodle named Punkin. He was a very tiny guy, but in no way sickly. He also didn't put our family into debt. He was a great rat hunter and often went on outdoor trips with us. A normal dog in a teeny tiny body.