Well, offhand I would say that if you want to figure out if someone is genuinely interested in you, as opposed to your vaginal ownership... don't fuck them right out of the gate.

I have sort of "set in stone" ways to figure out who is after pussy and who really likes me for me.

Whenever I start talking to a guy who seems nice, it just turns sexual and he starts sending me "hook-up" type messages.

Then that is where you end it. The second they start up with that shit. That is a giant red flag.

You are in a tough situation, age wise. The guys your age are thinking primarily with the little head, as opposed to the one that was actually designed for thinking. It's their sexual peak and some of them so not have the smarts to have control over all of their faculties. All you can do is hold on to your ideals and stick fast to your boundaries.

I don't even make sexual remarks or anything- I'm just friendly!

And honestly, a lot of young women aren't. And young males that are thinking with their little heads will interpret "friendly" as "good to go." Remember that their is a difference between being polite and being "friendly." Guys are going to interpret "friendly" as "interested."

Eventually you will find someone to respect them. It's just going to be a bumpy ride on the way and you are going to need to plow a few fields, first to find the one that works just right.

The only thing I find lacking is that I feel kind of lonely when I see my friends in caring, stable relationships. I'm happy for them, but I am also envious.

Be careful that your longing for this does not make you desperate for a relationship. Becoming desperate makes you an attractive target for those less that have fewer scruples. It lets down your defenses.

You are developing a set of values. You need to stand behind them and give them the respect that you want someone else to be giving them. Be patient. Be willing to stand by on hold, until someone is able to provide something you are looking for. Don't settle.