Can someone do a loyalty test on my boyfriend before he proposes?

I need a loyalty test done on my boyfriend... Can someone help?

I (18F) and my boyfriend (20M) have been dating for almost three years. I've helped him a lot through his personal and academic struggles. Like passing the reading benchmark, comforted him when he lost in fútbol, and practicing English in general. He's helped me with my Spanish.

I've seen him turn from a guy who had no plan in life to a man in the army. I went to his milestones, met his family, met his friends, the works.

I've heard that he's planning on proposing this Sunday.

The topic of marriage has been kind of been heavy for me because my mother married young and its a plethora of trauma. So i'm scared to fall into the same pattern.

I want to know if its time to fully dive in or if i should wait a few years. He's planning on proposing in front of our families. I've been having some doubts and fears.