I think I want to break up with my bf

So I've been with my bf like 9 months now

I love him and I know he loves me but there's just something missing

He treats me how any girl would want to be treated and yet I don't feel excited about the relationship

I get jealous of my single friends and their freedom

While I do almost everything for my bf, I feel so trapped

I think I fell into this relationship because I wanted one and now I feel like i've been with him 30 years and I'm 40 (I'm 20)

I feel like such an awful person, he deserves so much better than this

So I was just hoping for some advice and if anyone has been in this position before?

He's just such a lovely person, I don't want to hurt him but I know I will