Chicken took me 4 or 5 months. I really hard a hard time with anything dense and it hurt. Now 7 months out, I can handle anything.
So, the other thing that worked for me was cheese. Melted cheese. I would get smoked Mozzarella from trader joes and just melt it and eat it. And fresh Mozzarella worked, it's so soft. I would mush it up and add olive oil and vinegar. Feta cheese mixed with yogurt and spices worked too.
Oh and the other thing that worked quickly for me was Tofu. Now I generally don't like Tofu, but I would go to a Japanese restaurant and get Agedashi tofu which is basiclly tofu tempura in sauce. It's very soft because of the sauce.
Within 6 weeks, I could do shrimp salad with lots of mayo. But, chicken, was so hard and so was beef. Pork was easier.
It was very hard at first and I always had a tough stomach. But, my tummy was really unhappy with me. I remember, I had an olive and I love olives and even with just putting it in my mouth and having the watering mouth from the olive upset my tummy.