just tell her relationships are going to weigh your personal success down and now is just not the time for one
Not hard, be honest and tell her you feel like things are moving faster than you'd like and you just aren't ready to take that step in the relationship yet. Could also tell her you've got a lot on you're plate at moment and aren't sharing-for her sake.
assuming he hasn't told her the opposite in his communiques. Tell her an ex has contacted you and, due to unresolved issues, you owe it one more shot..
Tell her she isnt fat enough for you. Tell her to gain weight, and to check in after 40 more have been put on. Then dont pick up the call. (if youre feelin risky, wear a diaper and when yall are about to have sex let her know about your diaper fetish, complete with pooping and changing. If she doesnt run away, marry her.)
Only two dates? I was expecting several...if she's really attached now it's more her fault than yours. Just tell her that you're trying to work things out with your ex and you shouldn't have gone back to dating so quickly. And how do you know you're having sex on the third date?
Just stop making plans with her and then when she says "what's wrong" then tell her now that school started and you don't have any time for dating or for a relationship. Now, with that being said you are pathetic for using a fat chick to get over your own loneliness and insecurities over the summer. Lame.
I think this is good advice. tell her, you want it to work at first, but you are not feeling it, and it will be only more painful if you let the relationship go further, without feelin a chemistry and a connection with her.
You've only been on 3 dates? Seriously, it is WAY too early and she shouldn't think you are "committed" or "exclusive." You gave her a chance, but you just aren't feeling it. Be honest with her.