How do I know if my music is good if no one listens?

I've been making music for about 3 years now roughly and I don't know how to tell if my music is objectively good.

I love the projects that I finish and listen to them heaps in my car and in my headphones but how do I know if they're actually good and I don't just like it because I worked on it and I know what's coming?

It makes it even harder to tell when no one listens to anything I share... and which makes it even more difficult to get constructive feedback or any for that matter