That is a most interesting question! Living with regrets is certainly not healthy and acceptance with grace leads to peace and allowing love into your life without judgement leads to amazing relationships all round....
HOWEVER - it has taken me 15 years to get to this place!!
Lets face it - it a CULT that dominated our every thought and action, lead us up the garden path in an all encompassing fairy-tale / nightmare with hideous rules and consequences, filled our lives with judgment of others and gave us a superior attitude and then to finally figure out we were not special leaves a big hole full of every range of feeling and emotion and for some of us it takes a while to work through.
Yep it was a waste of time but through that now so onwards and upwards eh?