Driving halfway across country alone, should i tell my ex?

he is acting wierd and distant (after hes spent the last 6 months trying to get me back). but he has no clue I am leaving to Texas! we live in upstate NY. I am only 22, but i need a new change to get away from the BS. this is a huge trip for me, i am really scared! Should i tell him!? he has no clue about any of this...i am so confused