I Dont Know What To Do…

Hi everyone ! So im really nervous about getting my surgery on the 22nd of January. I am 21 and autistic, and have “weird” food preferences and food sensitivity due to textures and whatnot because of the autism (thats the only reason why I mentioned being autistic lol). I have probably never ate a real fruit or vegetable a day in my life… That doesnt mean I just pig out, so please refrain from mean or negative comments about my eating habits… But I am extremely nervous about getting surgery as the post op diet is so based around fruits and veggies. What can I do??? Someone please please help. I talked to my surgeon and nutritionist about this and they dont seem to take me seriously on my concerns, they always just kinda pass over the topic and say something like “I have to get over it” but its just not that simple. Someone please help!