how do i let him know, without coming off as creepy!!??

My boyfriend, it turns out, has some problems with drugs. I've known him two months, been dating him for a about a week and half. i know i sound creepy and stalker-ish. I'm not claiming love or marriage. i really really like him though! Anyway, he is going to rehab, and told me he wanted me to be happy and not to wait for him. but i am and i want him to know i am. but i can't think of anything to say that doesn't make me sound weird. Also i want to do something sweet for him before he goes but i have no money or any idea what to do. what would a guy like in this situation? I just like him so damn much and. from what he says, he feels the same. and we barely got a chance. I'm glad he is gonna get better though... some ideas please? I'm distressed. !???????