The idea of something and the actuality are often different things.
Having sex outside a relationship doesn't offer you any more emotional or physical protection (and sometimes less), than sex IN a relationship.
In addition, I'm a bit wary of some of what you've said here. What exactly is the context in which you're agreeing to have sex with various people in the future? In other words, I don't imagine you're just sitting around, and someone asks you "Hey, wanna bonk sometime?" and then others ask the same. So, what's going on exactly?
Look, if you're not emotioanlly ready for a relationship yet because you're still wary or fragile, that's normal and fine. But being emotionally fragile is about the worst state to start intiating casual sex that there is, let alone carrying it though (and if you're agreeing to future sex with folks on the fly that you may or may not intend on pursing, you're setting yourself up for more sexual harassment problems, chica).
So, why not take the time for yourself you need, period, without also agreeing to other things that probably will keep you hurting or get you hurt further as well?
Editor and Founder, Scarleteen
My epitaph should read: "She worked herself into this ground."
-- Kay Bailey Hutchinson