My(22m) girlfriend(23f) wants to buy a house - we've never lived together - should we rent first?

My girlfriend and I have been together for just over 4 years, we're 22 and 23 years old respectively. We both work full time and have been saving for a deposit for a house for a while now. However, after finding out my entire family doesn't support the idea of us buying a house and would rather we rent first as we've never lived together, it's made me doubt the whole thing.

I'm at a loss of what to do, I've mentioned renting before and she has never liked the idea since it will be 'paying someone elses mortgage', which I can understand.