Love or convenience?

My boyfriend '44M', and me '43F' have been together for 4 years. I was in the process of buying a house when we were dating and bought and moved in my new house. About 6 months later he moves in and explains it would be "temporary" because he too would like to buy a house. Its been 4 years and now he is getting serious about buying a home. Im pretty sure we will grow apart when he moves out. But none of that concerns him at all when i talk about it. My question is , would you have let him move in with you knowing it wasnt permanent? And how serious would you have let this relationship get knowing this? I feel like ive spent 4 years of my life , which is my longest relationship, giving to this relationship to have him just up and leave without a care in the world. Im thinking he moved in so he could save up some money to buy his own house. But its not like i havent benefitted by his added income. But is this more a relationship of convenience??