Based on the minimal context and my own personal experience, I'd have to interpret that as basically "severely unpleasant or irritating to deal with; a person who is rude, unpleasant, etc." Essentially, the speaker has left out a few words (a simple case of literary/poetic license, I assume) and converted "bitch" from a noun to an adjective, but kept the same meaning. You should be able to insert "much of a" right in there and keep the same meaning, i.e:
...you're too much of a bitch to get a job...
Another, equally valid, equally un-modifying, and perhaps more helpful way of paraphrasing would be to simply add a "y" to the end of the word, i.e:
...you're too bitchy to get a job...
So, long and short, the speaker just means, "No one would ever hire you because you're an utterly unbearable person." That's how I read it, anyway.