Find yourself a task or a hobby or something else that will occupy your mind and your time.
You need to grieve ~ because grief is what one feels when a special relationship ends ~ and, in my opinion, one thing that helps in the grieving process is involving yourself in something positive and time consuming.
Work for a charity; write a book; start studying a new subject; join a club; take up gardening; go travelling; link up with family and old friends; go somewhere where you might make new friends.
Accept that this is over and cry about it; talk about it; write about it, but do other things too!
Writing poetry can be very therapeutic (as can gardening).
Good luck & take care.
