,....
So my advice is this: start to be more distant so he can "feel" what is happening, refuse to go out with him and lately tell him you don't feel the relationship have a chance for future, but also tell him the good things you saw in him and be friendly.
Ack! NO!!!! Don't do the "slow fade" - distancing thing!!! Read the "women in their caves" thread to see how HURTFUL that is!