First off I hope u feel better soon and please do not get discouraged.
Prove the docs wrong and get ur Protein in I know u can do it! It's extremely hard but you will feel so much better. Just focus all day on recovery and drinking. I'm 5 weeks post op and I have no problem getting 100 + grams protein but at first it was a fight. Try getting powder and adding as little Water as possible maybe only 6 oz so it's less for u to drink but u also can get ur protein in. If u drink them with soy or almond milk that also ups ur protein, carbs, and sugar but in a good way. Or if u have a fruity kind u can add it to ur g2.
Another tip, natural Peanut Butter. If u heat up soon just slightly.. About a tablespoon and try and suck on that for a while that's already about 100 calories and good sugars and fats. It goes down fairly easy.
I hope everything works out I had the exact same problems I passed out twice in my 3rd week and I was embaraased to tell anyone because i knew they would say something negative. Just know that u did make the right decision. Nothing worth having in life is easy and this is no exception. U r working through a battle for your health and you will win!