He wants to buy a house, but I’m scared of waiting for another proposal that never comes

Hi everyone.
I honestly never thought I’d be back here.

I spent 7 years with my ex, waiting for a proposal that never came. Marriage was always something I wanted, but he never seemed interested, and eventually I left the relationship. I left this subreddit too, thinking I’d never need it again.

Now I’m almost 2 years into a relationship with my current boyfriend, and I don’t know if what I’m feeling is leftover trauma from my previous relationship or if my concerns are actually valid.

We’re both in our late twenties. Early on I told him that getting married one day is important to me. Around our first anniversary he said he felt it was too early to get engaged, which I completely understood. But that same week he started talking about buying a house together and how we’d qualify for a much larger mortgage if we bought together instead of him buying alone.
Something about that really scared me.

I told him I was afraid I’d end up in the same situation as before, waiting years for a proposal that never comes. Instead of reassuring me, it turned into an argument. At one point he said, “Well, you’re not really helping your case.” I cried for days afterward because it hit a very sore spot.

Lately he’s been encouraging me to sell my newer BMW so we can qualify for an even bigger mortgage together.
The thing is… I’m pretty certain I don’t want to buy a house unless we’re at least engaged. To me, buying a home together is an enormous commitment, and after what happened in my last relationship, I’m terrified of tying myself financially to someone while quietly hoping a proposal will eventually happen.
Ironically, my boyfriend has even said that marriage feels like a bigger commitment than buying a house, which only confuses me more. If marriage is the bigger commitment, why are we ready for the house but not at least an engagement?

Has anyone else been in a similar situation? Did you wait? Did you set a boundary? How did it turn out?
I’m genuinely trying not to compare my boyfriend to my ex, but it’s hard not to be afraid of repeating the same story.