不同居决不该结婚，不同居你怎么能真正了解他呢。

我觉得他提起付mortgage和insurance是很正常很负责的表现啊。难道你能假设该他全付吗？一家人还的夫妻共付mortgage和utility呢，我觉得他主动包付很generous啊。既然你offer付房租，他就会想想，This shows he is honest. How else do you want him to do? 象中国人一样做面子工程，嘴上假客气吗？ If he refuses your rent, you should offer to pay some utility. After all, it does cost more utility to have two people living in a house than one person.

我会share the cost, and keep financially independent, unless he is super rich and does not care about your contribution--I doubted from his reaction to your rent offer. Before marriage, I would feel better to have my own independence.