I do want to say though that I don't go willy nilly for just anyone! I'm a beautiful girl and I get a lot of attention.

My apologies I realize I was very unclear re:willy nilly falling at feet.

What I was trying to convey is that we need to
discern who is actually a good fit for us, and if they will truely compliments us, before graciously falling at their feet.
A nice personality and good looks only go so far, people are like puzzles and we need complimentary pieces in order to fit comfortably in eachother's lives.

Simple example, a major reason why my bf has always been super attractive to me (even before I realized I was actually attracted TO him) was the fact that he doesn't BS me.
He tells me the truth, as it is, in living colour, no sugarcoat. I need these type of characters in my close relationships because I APPRECIATE being called out on my BS, it helps keep me grounded, and its easier to establish trust within these relationships.
When BS is called from a trusted source it forces me to take a step back, and be as introspective as possible, which in turn shortens my crazy period. Complimentary!

I think that he and I have a very different idea of what a casual relationship is.

See what I mean about puzzle pieces? I'm actually very pedantic regarding clarity in relationships (because things easily get murky for me) so even though it sounds clinical, I discuss expectations, boundaries, and definitions thereof early on. Kind of like how when (traditionally) a young daughter brings a guy home and daddy goes "What is your intention with my daughter?"... uncomfortable sure, but its always worked for me and its much easier to navigate than say, divulging your dx too soon. This cards on the table thing I practice has ensure that we both clearly know where we stand and what the "rules" are. No misunderstandings... Communication is key afterall

I think that he thinks that a casual relationship means that he gets to call all of the shots and completely ignore me when he feels like it. I think that a casual relationship means that we can take it slow, but that communication, respect, and consideration is still a must.

And then you get people like myself who have yet another differing idea of what it is... To me its got nothing to do with speed, but more about enjoying and embracing the here and now. To me, its not making an effort to act as if one is in a relationship, (I see you when I see you) because both have agreed and understood its going nowhere, yet both parties want to enjoy the present together.
Of course communication, respect and consideration is a must, but on a much smaller scale than when in a romantic relationship... Again, that's just my view and I'm stating it solely to concur that you may very well be right about you 2 having differing definitions, and to reiterate how the right type of communication early on is vital.

I'm not unlovable. I just feel disposable in this society that has a "is it breaking, don't fix it, throw it away" ideology and knowing that there are plenty of women who will settle.

But how does this actually pertain to you? You are obviously not the type to settle so why bother about who or what the settling women will be settling for in the end?
Its 2 vastly different demographics with very different "target markets", so zero competition... no?

Because if I understand you correctly, society has conditioned people to throw out what's broken... and then those very men who act like people are disposable go out and find the women who will settle for them...
Please correct me if I'm misunderstanding, because from this angle, that thought process is illogical. We refuse to settle, we want what we are worth, and those who are actually worthy of us won't treat us like we're disposable... Thus absolutely no "competition" from "settlers"...

I fear that all of the good ones will be gone by the time that I can settle down. I still have a year long contract in China and two degrees to earn.

Who's to say you won't find love in China? Who's to say you won't find a kindred spirit there also trying to carve out a life for himself so far away from home? Who's to say you will not find someone who's been living at the same pace as you? This fear is unfounded, please don't feed it

I want companionship later and during these intervals (though I don't need it constantly), but everyone is pairing off now...

This train of thought led to much of my unhappiness, comparing myself to my peers brought only misery. In many ways I am and have always been verrry far "behind" in life, but I've walked a very different path, had many unplanned and traumatic pitstops along the way. Had boulders thrown infront of me, that I had to figure out how to move on my own. So logically its kind of impossible for me to be at the same point in the road, when we're driving on very different tracks...
Since accepting that my pace and path has been different, its much easier to not compare myself to my peers. Which means I'm much more content with where I am and with where I'm "eventually" headed.