Hi Cudbear,
That's a really interesting question! One way I like to frame the answer for people is to talk about how love and lust are not quite as separate as we tend to think of them being. I actually go into a ton of detail about why that is here:
https://www.scarleteen.com/article/advi ... vs_lusting. The short version is: we tend to think of lust as only being about a person's physical traits, but for the vast majority of people, lust has an emotional component as well, even if that's just "I trust this person enough to be sexual with them" (or, conversely, "I'd be super into having sex with this person if their personality weren't like kryptonite to me"). In other words, our feelings about sexual partners aren't either lust OR love/like. They can be a mixture of both. Does that make sense?
When it comes to telling if you like a person, some general things to look for are: you enjoy being around them, and want to be around the often, they make you feel happy and comfortable, and you want to get to know them even better. Love is a bit harder to define, because it is such a personal thing and a word whose definition has been argued over for a long, long, long time. Heather does a really good job tackling an answer in this piece:
Love Letter. In it, they quote bell hooks and add.
"Love is a combination of six ingredients: care, commitment, knowledge, responsibility, respect and trust." It may be obvious (which may be why she didn't say it) but to her list I'd add connectivity: I'd say love is about connecting and being connected to ourselves, to who we love, to everything. There's an energy to being deeply connected that once you feel, you'll recognize ever after."