Audrey Beauregarde:
According to Dr. Feeder's amazing article Deciding to Get Fat, if you want to gain but feel guilty about it, then you aren't ready yet. How have you been able to get past this step? I had recently tried to just give in, but my guilt really took hold and I wasn't able to continue.
Used to be a gainer forever ago. I had a lot of guilt because my mother would body shame me a lot. To put it bluntly, you gotta get over it.
Identify why you feel guilty, and work on letting go. It might take some time, but you can do it.