Marriage without being in love ?

So I’m not worried about this right now. I’m the future I could be.

Basically my bf and I make comments about our future together or like wanting to marry each other one day etc. We have been dating almost a year. Im not some special person though, like his last two gfs who were really serious and they dated long long times, he was the same way like wanting to get engaged and married and he was like so serious and genuinely thought they would at the time.

I don’t mind that kind of talk. I think it’s nice and shows he sees a future. He wasn’t in love with her first serious gf but was with his second. And I know he’s not in love with me. And no I’m not in love with him right now. That’s why I’m not like freaking out.

I’m just wondering, how could you marry someone without being in love with the person? Genuine question. I’ve never been in love with a person before. But I don’t want to marry anyone if I’m not in love or they’re not in love with me.

And Ik he’s not cuz I subtly asked and he neither said yes or no, just joked and told me to cut it out and that he loves me. Which is an answer in itself.

What’s the difference between being in love and just normal love ??