Imagine your bending the note with your third finger, once its fully bend and your about to release it, let the string lift from the fret board but keep your finger touching it lightly to mute it.
Also with bend its good practice and technique to "get as many fingers behind the bend as possible" (Billy Gibbons) If your bending the 14th fret with you third finger then your first and second fingers could fret the 13th and 12th frets, if they arent being used. This gives you more control I feel.
Also smaller gauge strings, and tuning your guitar half a step down (which is common in rock bands) makes the strings slacker and easier to bend.