In my case ILYBNILWY really meant "I'm afraid that YOU don't really love me in a romantic way because you don't pursue me and lust after me the way you used to so I'm not going to love you either."
As I read that I had flashbacks to the night my W told me the ILYBNILWY because she also went on to say that I don't pursue or lust after her like I used to as well.
