My life is meant to be lived. I'm alive for a very short time. I refuse to spend it looking over my shoulder; second guessing everything. If I do something stupid or harmful I made amends (or try too). I redeem myself for my own peace of mind.
Look it boils down to this: what does every faith on the planet teach? I'm not typing about the differences or whose god is stronger or better, I'm talking mythos - they all teach that it's all about how we treat each other. That's what it all boils down too.
I'm mortal. Of course I have regrets. I don't live for the moment (like dogs - or do they... I have doubts about that) I don't believe regrets are "negative". They're a part of life. We've all had missed opportunities. We've all treated someone poorly. It's life.
If I step out of the house right now and get hit by a bus, it's the living; they'll have to sort my life out. But I hope I have the luxury of facing death with time to reflect on my own life and realize, hopefully, that I lived; had a great time; and left my mark.