As far as sight reading goes, you'll never be good enough. Meaning that it will be a lifelong task to improve. It's a skill and as such learning is a process, not an event. Get any written books you and find (cello, trombone, bassoon, bass, orchestral funk, rock , jazz) and play them as slowly as you need to to get them right. That means giving the sixteenth note a beat at 60bpm or slower. Speed will come in time. Know the neck, know it as well as you possibly can. Know all your scales in all the forms in all the places on the neck. Take your time, but work on it every day. Get with a group that reads, any kind of group, community band, church, theater, jazz whatever. Read music, read every day, read with good musicians.
As far as the audition(s) go. Play things you can play well. No one gives points for difficult music played poorly. Remember, not only are you showing them what you can do, but you're showing them you know what being prepared is. Better to be excellent at simple things that clumsy at things you can't yet play.
As for the school. Know what your goals are. Unless you plan to teach in a school you may not need to have a diploma or finish the degree. Your experience and knowledge might be more important than the paperwork. With that in mind, since you are in the college, you might consider training in some subject that will guarantee an income greater than what music will offer. Keep in mind that the school is a business selling education to people willing to pay for it. It is NOT the job of the school to insure that your training will lead to employment or the kind of life you want to lead, that's your job. Know what you're getting into.
Good luck. And remember.... every minute you aren't practicing to get the best gig, someone else IS. That beer can wait. And no matter how great she looks, someone else is tired of her crap, get back to work, time is short.
