I am 32 and have had this since I was about 12 I think!. I am replying to you becuase mine started in almost the same way. I was on a holiday and developed extremely chapped lips from sailing - the rest is history....
Anyway in the begining I mean first 5 or so years if I left the deadskin on the colour of it would be yellow/ green and would be totally crusted on the lips.
After years of manily leaving it alone mine do not go yellow/green but just get a build up of clear deadskin which needs to come off. I do this by moisturising all the time and being very gentle.
The key me is to not put any stress on the lips ( physical ) and they have got better ( slowly over time ).
By the way how have you managed your life, are you married for example with this condition?