scubadiver

I am not a lawyer, so don't consider this legal advice:

Are you in Ontario? First of all you are not common-law in Ontario until you have cohabited for 3 years (even though you can say you're common law on your taxes after 1 year), in BC it is 2 years cohabitation. Cohabitation means living together, whether you rent or own.

Separation comes under provincial jurisdiction.

If, as you say you purchased the house 50/50 and you are both on title you are both rightfully entitled to 50%. However, you could both argue for the value of home improvements if you made any.

Common law separation DOES provide for support payments - but even if you are in BC and legally common law, you haven't been common law for very long. So your payments would be so small and for such a short period that it's not worth her going to court over.