When I lived near you Nero, I sometimes used to get the 197 bus from the library to East Croydon - it does drag, and isn't pretty but has the benefit of being close to home and avoiding schleppage But usually just went to London Bridge and then changed - ultmately it's just easiest. Travelling to Forest Hill, Change, West Croydon, Change, East Croydon, Change and the Brighton has too many steps that can go wrong for me