I feel you, i also went through the same way with my old-best-friend at mid school. We used to talk so often yet now we barely talk anymore, only once in a while. Even when we meet and hang out, the connection just isnt there anymore. She's on phone almost all the time yet it takes days to give me 4 words reply. At first it was bugging me but now i dont care anymore lol. Well the point is i cant try with ppl who dont try. If we talk, good. If not, it doesnt matter. So i just let it go~