The one who left you, hardly wants you to suffer. Don't torment yourself with memories, thinking of a romantic date, resurrecting his image. Favorite person to mentally let go.
Letting go means not to forget but to accept, accept. However, the way of life will have to change, if not immediately, but you should form new habits and rituals not related to the departed loved ones.
Allow yourself the tears, they ease the soul. And let the people you are doing fine, save yourself the suffering is not worth it. Imagine that with tears the pain goes away.
Share your experiences with loved ones, you can talk to the psychologist. Not to withdraw into themselves, communicate, and abstract themes.
Try to observe the mode of the day, do not refuse food, even if you have no appetite. Definitely sleep if you suffer from insomnia, drink a natural sedative. Sleep is your most important medicine.
If you managed to take time off to recover, it is not necessary to indulge in idleness in an embrace with a bottle of wine. Alcohol relieves the pain only for a while, be careful with it.
Connect with nature, get a pet. Our smaller brethren wonderfully to soothe, distract and comfort. They love us selflessly and expect nothing in return.
To the question "why it took" no answer, do not look for it. The fathers of the Church say that man calls God, and you are still in this world. If you are religious, the belief that the meeting with the beloved will one day happen in heaven, must help.
In the end, each of us has to accept the fact that death is inevitable. This knowledge helps to live allotted period brightly, without indulging in sorrow which, as we know from the Bible that many were killed, but one is not yet saved.
Help others in need. There are people who need you, don't turn away from them, feel necessary. And soon life will give you a new incentive to go forward.