I’m not at all sure that deep feelings ever really goes away. It might get hidden under a pile of crap but it's always there, ever-present. Whether it actually presents at the moment as sexual attraction or not might wax and wane, but the feelings will still be there and sexual attraction can be rekindled.
The trick is to get the other person to see you in a new light. Show a different part of your personality to him, give him something he hasn't seen from you yet.
We're attracted to the new and shiny, the old and dull just won't motivate. So make yourself new and shiny.