Rather
Part of speech: adverb
Definition: More quickly; sooner, earlier. Used to specify a choice or preference; preferably. Used to introduce a contradiction; on the contrary. to introduce a qualification or clarification; more precisely. (Now usually preceded by or.) Somewhat, fairly.
Example sentence: I'd rather be hated for who I am, than loved for who I am not.
Instead
Part of speech: adverb
Definition: In the place of something (usually mentioned earlier); as a substitute or alternative
Example sentence: School was a waste of time for me. I was bored and left at 16. I started taking correspondence courses at college instead. I did incredibly well. I won an award for my grades.