Non-purchasing Occupant Affect on Co-op App

I suspect it will depend a bit on how tightly your finances are connected to your partner's. Will you contribute to the monthly costs and upkeep of the apartment? Does your income play a part in showing that they can be covered easily? Does your partner contribute to your living costs (beyond sharing the apartment), or pay your outstanding debts if any?

You don't have to answer all that here, but those are the sorts of issues that might come into play -- trying to show that she's a separate financial entity, that your financial record is less material, and that the board should focus on the idea that you're a nice person, considerate of neighbors, good to live with, etc.