Sure it is possible, but what is the purpose of this? All you have explained is having a file with some contacts in it and some associated numbers, which otherwise wont have any functionality at all.
So, what is the purpose of this data file and these numbers? What are they for? And what do you mean with
"infinite uses"?
"Uses" for what?
"which will add the current guy you're chatting with into the text file with a value of 0/5". => What value? 0 or 5? You can't have both...
You need far more to explain and far more details if you want someone to make this for you though.