No-one notices the cobwebs in a welcoming home that's filled with love and laughter and, as far as I'm aware, no-one's last words have been 'I wish I'd done more weeding/housework/ironing/cleaned the oven every week'.
Some find it easier to open their hearts and accept others, with all of their peculiar foibiles and idiosyncrasies, than it is to accept themselves for the equally unique and marvellous individuals they are .
We move on from the past by leaving it behind and separating our true and constant selves from our transient thoughts is embodied in the Buddhist practice of mindfulness which is now extolled by the NHS:
www.nhs.uk/conditions/stress-anxiety-depression/pages/mindfulness.aspx
CBT and talking therapies can be effective tools in resolving feelings of guilt but we can go some way to shortcut longer processes by wholeheartedly embracing the fact that we are works in progress for whom perfection is an unattainable goal - those who are perfect (in their own minds) are invariably crashing bores that people cross the street to avoid 
Feeling 'good enough' is about accepting that we are no less worthy than anyone else and that we are occupying our rightful places in this world, just as they are doing.
Those who haven't set out with malice aforethought to cause harm to others, and those who haven't accidentally caused harm to others by committing an unlawful act such as drink driving, have nothing to feel guilty for and, providing we learn from them, minor misdemeanours rarely warrant more than a few minutes of remorsefulness and a resolve to avoid repeating the behaviour.
Once we've begun to kick the guilt habit into touch by identifying, exploring, and dismantling our fears we may find ourselves feeling guilty for not feeling guilty, but once we've embarked on the path of liberation that leads to a guilt free state of mind our increasing heightened awarerness will serve to ensure there's no turning back.
Given the human condition, this is not to say it's possible to reach the end of a long life without having experienced feelings of regret but we should be able to reach some accomodation with them whereby, as the song says, they're too few to mention.