Numerous reasons owner has to pay rent to another owner. In the context of a pending dissolution these are called Watts Credits. If a partition action there are three reasons: agreement, ouster, or equity. Settled CA case law here.
Question is whether action is an ouster. That is not settled, though unpublished cases indicate this would constitute ouster.
It is better to actually answer questions people ask, it guides advice better. I will assume you are BF suing for partition Pro per.
To start, you will always have more access to the facts and, apparently, to the case law on the specific facts. The advantage of Pro per's is that they don't know anything so they look up everything if they have the time. Any tidbit, any hint of an argument and they are all over it. Sometimes, under some circumstances, when some thing, has some value, and a court with some sympathy, had some mention, in a way that somehow helps the argument--SLAM DUNK! Usually, generalities win without skilled attorneys looking to push the law forward.
While I know you were answering a question, put "Watts Credits" out of your mind. You are not married. Get over it, move on. There is no way you will convince a court, unless they are desperately trying to help a person with a domestic violence order against them, is not going there. If they do, they should be disbarred. We are not talking of community property. The nonsense that would ensue from such rights in your case would make a mockery of the law. If you have a case that used it as justification under facts near yours, let me know. I will start a committee for the removal for the silly judge.
You obviously have no agreement, you obviously have no equity argument (If you want to claim this, give me your argument. To me it seems clear.), and so you go for ouster.
Under basic common law, there is no "ouster". I admit it is a clever argument. But, there are two problems. One is the basic issue of ouster. While you want to place the onus on the person (owner) who opened litigation, in reality, it is the judge who decided the remedy. Also, we get to the basic theory of "possession". While the judge's order might prevent all realities of "possession", I think it does not. That YOU can't stay there (For any of a number of reasons. Stay away from the plaintiff. Stay away from the residence. Whatever.) does not mean you have lost "possession". You may have lost parts of possession, depending on the order, but you have not lost them all. By my guess of how the order reads, you have not lost any real possession. You just can't be there when she is there as you have to stay a certain distance away.
But, answer all the questions previously asked. It might help the gestalt give something that helps you. To be fair, a certain percentage will dislike the facts already provided and will do some stomping. Suck it up, buttercup, people who are serious about being together get married. Living together does not give the same rights in general. (I say in general as I used to have a certain amount of business from gay couples who wanted to legally bind themselves to each other as in marriage. The sad part was you could not quite do it. At some point it is an argument. The good part is that two people would come together out of love with full understanding of what legal duties and responsibilities were created a construct that could accomplish what they wanted.) You did not do that. You moved in with your gal and lived as though how you lived was going to be fair in some way. You broke up. "You guys" are done. Now you are in litigation.
Sucks to be you. I suggest an attorney. They know how to help you best. I know you can't afford it, but, don't you want an expert on your side? (This is the best advantage to the unmarried. You don't have to pay for her attorney.)
Bottom line? Argue "ouster" to me and I would make you cry like a little girl. If she does not have an attorney, it depends on the judge.
