You are going to yearn after him and miss him as long as you keep thinking about him, playing songs that remind you of him, go places that remind you of him. In other words, you have to make yourself get over him. When thoughts of him pop in your head, don’t dwell on them, start thinking of other things. Don’t let yourself pine over him. Keep busy with other people and things and eventually you will realize an entire day has gone by that you didn’t think of him. Then a week, then a month. It will then be “out of sight, out of mind.”