I'm mad that my girlfriend didn't let me get us a dog
Why didn't she let you get a dog? What would happen if you did?
She didn't want my dog being around the asshole next door. She only wanted it around her and me.
Dogs can be quite a responsibility, maybe it is better this way you don't have one. She sounds like a possessive type too, even with animals.
My girl is not a dog lover. I'm a dog lover because I understand dogs better. I am a good trainer too with them.
I understand that you enjoy dogs, but if your girlfriend doesn't that might be a problem. If you can try to reason with her she might be able to get over her issues. If not you may have to accept that you won't be able to have a dog while living with her.