Drielly,
I do not have near the extent of the fear of choking that you have, and its quite common in anxiety disorders. I do occasionally have the "can't swallow, it's a struggle to get it down" feeling, but only happens when I'm anxious. I set it aside to eat later when I'm not. You have gotten into the mode of the anticipatory anxiety of eating, knowing you have to to , and causing more thoughts about the next meal. I do recall reading in one of a zillion panic books, that CBT is very helpful in this area, but was interesting to read that one patient seeing a CB Therapist, asked a patient to chew on a cracker, they started to feel the immense anxiety, and the therapist told them, I asked you to chew, not swallow. It was kind of a revelation that they were already causing more anxiety of the thought, when asked to chew only. The therapist was doing a gradual progression of a step of just practice chewing, have something very light in your mouth. Perhaps this might be something you might want to try.
It is commendable that you are increasing your intake, and you should be proud of this achievement, you are taking the right approach, just need to be able to have some help with the actually eating part. You are progressing good, don't dwell on how it came about, just that it is another curve ball with anxiety, some things we get over certain phobias, only for a new one to arise. (Or in my case, it has, one thing that had me frightened most of life, totally left me, and a new one came in)