1) does she really mean it when she says that she can't say its never going to happen again?
By her dating other guys, getting serious with another-- well I say she really means it when she says it won't happen again. Besides she is 18. She doesn't even have her head on straight- going clubbing after a breakup and making out with random men is a sign of that!
2) If she does get with a guy... is there still hope for me in the future? Should I be there to pick up the pieces if/when it fails?
She is with a guy; two actually [that you know of], and the one seems to be getting serious, he did turn down a job "for her". The fact that you've already decided destined her future relationships to fail really makes me question your love for her.
If you love someone you let them go, even if it means they are happy with someone else.
Since you were her first boyfriend I really doubt the fact that she was your "real" love. So many people on this forum could swear up and down that they're first mate was their true love until they woke up and saw that it was just another passing stage in life.
It's time to buck-up. It's over and that is that.
Sarah