Are you afraid of failing herself or yourself if you be with her?
Everyone is a work in progress to some degree. So, you have defined your area for improvement.
Now, instead of hindering yourself, why not try and achieve your dreams and goals while being conscientious of your shortcomings?
yep, being in a relationship requires too much work, and if I focus on her I can't focus on myself which is near impossible for me to do, plus her ass is pretty nice but its not outrageously hot, and ass is very very important for me
also I don't want to be trapped, fuck that shit
p.s. i usually say this to my lady friends in an attempt to charm them

"just be nice to me baby"