There is a difference between validating someone's grief (and there is no better validation than sharing a similar personal experience) and actually encouraging the expression of grief by framing the experience as an exceptionally bad one. The best way to deal with a negative experience is to frame is as a normal occurrence of life, and not as some extraordinary misfortune.
If you're an alcoholic at the end of your rope, you don't go to a psychologist who will tell you that he understands your pain because your life is extraordinarily bad; you'll go to the AA where you'll hang out with a lot of people for whom your experience is normal, and yet managed to leave it entirely behind. (As much as it's allowed by the dynamics of addiction, of course).