Are we good for a rat and a sheep??

You two may need to work on your relationship more to make it a happy one. You two have very different personalites. They both get along well at home, but the problems will come out when they go out. Rat likes nightclubs or so, but the sheep want to enjoy the beauty of nature. Sheep prefer a quite quiet life, but rat do not like it. Sheep will feel fruastrated about the rat's energy and need for activities. So they can be a good friends, but it is hard for them to be lovers.
However, Chinese astrology can just be as reference and not all of them are correct, if you love each other, just stay together.