Pay attention to the ends of verbs. It's 起こるはずがない, not 起こったはずがない. Also, the occurrence of a miracle is not what the condition is placed on here. I think maybe you haven't learned certain elements of もしかして奇跡起こらないかななんて. ~ないかな can be used as a wish that something will happen, like 彼女、早く来ないかな ("I wish my girlfriend would get here soon."). なんて is a quoting particle in this instance. The verb is probably 思う, since the そうでも in the next sentence refers back to もしかして奇跡起こらないかななんて. Next, a couple of hints:
なければ -- conditional form of ない
思わない -> 思わなければ (from simple negation to conditional negation -- "not think" to "if (I) don't think)
やっていられない is a set expression meaning something like "get along" or maybe even "survive" in some cases, although I don't think it means "survive" like 生き残る or 生き延びる do, just a dramatic way of saying something (like "I can't survive without my designer shoes!" for example).