Reliving our lives? But we can't! So what is the point of worrying about reliving it--- like when Buddha was responding to someone that asked him how did the world/universe start, Buddha replied that the person asking the question was like a man who has just had an arrow fired into his leg and asked why is there an arrow in my leg rather than how do I get this arrow out of my leg.
If there is anything we wish we did differently, we could do Vajrasattva to help purify it. Do I wish I had met the dharma at an earlier age--- like birth--- and practiced it really well from childhood? Yes, but I was an adult, so I can do Vajrasattva for the karmas that didn't give me an immediate precious human rebirth and aspiration prayers, and of course, since I rely on Dorje Shugden, I can also ask for his help to make the conditions good for my practice now, and help with realizations so I can make this life meaningful. So, while it is good if we have regrets, really, because they are one of the four opponent powers, we can really rejoice that we now have the opportunity to purify our karma and continue our daily practices. Of course, if we hurt someone, in the past or acted inappropriately we can try to make amends.
