So DP is moving in soon to live with me and my DC (who are here half the week). I take home £2500 a month and he takes home £1700. He has no dependents. His parents think he should be paying 50% on all bills and mortgage payments but I don't think this is fair. I earn more than he does so if he pays 50% he is effectively paying more in terms of what is left of his wage compared to how much I will have left. I think he should pay a percentage of the bills and mortgage repayment relevant to our incomes ie I pay more because I earn more. I discussed it with my brother (only living relative) to gain his view and he raised his eyebrows and said well sis that is very generous of you, he's a lucky guy.
So my question is, am I being fair and appropriate or overly generous?