It is the experience, not the proof, which is important. Generally, when someone asks you to prove your love, you tend to think in terms of physical acts you could perform for that person. Those two notions are unrelated. You can do something good for a person without having much genuine love. Past-life memory, like love, is an experience to be enjoyed and to be embraced for growth and spiritual development.
Critics question whether the retrieving of past life memories is authentic.
The names, places, and dates could have been recalled from existing records which had been heard or read and then forgotten by the conscious mind in the current life. They also add that so-called memories come from imagination or fantasy. Events can be authentic without being recalled at will. One reason for the belief in the theory of past lives is the need to learn the multiple lessons on the journey toward wholeness. Some traditional therapists find the idea of past-life regression to be too implausible or radical to warrant attention.