I'm in need of an elastic. No plastic.
If your dreads are as thick and unruly as you say I don't know that an elastic of any sort will help you. What's stopping cloth wraps from working for you? Do they slide off?
Ignore the pretty girls. After you graduate they become completely irrelevant unless they were also the smart girls. And the beauty they rely on to feel better than others is going to fade fast unless they prop it up with surgery.
You have to change the way you think about the things people say. Insults from people who don't understand dreads are the same as compliments from those who do understand them as far as I'm concerned. If they're giving me funny looks about my hair that means I'm on the right track.
A drunk guy on a bike told me that I looked like I should be swinging from the trees with Tarzan. My friend was a bit offended on my behalf but I just laughed and said thank you. Really, that's the look I'm going for if you think about it.
If someone tries to use Bob Marley as an insult you should laugh at their sad attempts to hurt you. Bob Marley had fantastic hair and made some great music. How can it possibly be bad to be compared to him in that way? If they call you Medusa thank them for the halloween costume suggestions.
Another thing to keep in mind is that going out of your way to comment on someones appearance in a negative manner is immature. They are going out of their way to hurt you. Why even care about the opinions of people like that?
I'm a few months ahead of you with a mix of twist and rip and natural. You're right on schedule for the "worst" of it. :D. They'll really start tightening up soon enough. The dreads I twist and ripped are getting quite solid now at 7 months in.
I try to limit my separating to once a week unless I notice something serious happening. If you are worried about separating watch Baba's video on the subject.