Roommates, whether romantic or unromantic, ought to be splitting expenses in half except for when there is an uneven expenditure. Like, if one person uses all the hot water and runs energy costs up, they either have to put up with chiding or pay up.

I won’t bother comparing situations with an anecdote (although, it would be easy and I agree with everyone that has done it on this post), but your partner is more than capable of splitting the cost of living, or they need to move out. This is from a financial position. I’m trying really hard not to give relationship advice, but from a partnership, this is whacky. Expenses of living are meant to be shared or there is an imbalance that doesn’t sit well in an age of equality (so maybe political, but hopefully still away from relationship advice?).

Financial advise recommends 30% of income to go towards housing, if I remember correctly. So, I think that she’s more than capable or staying with you is out of budget.