What's the lowest amount of fats I can go to and still be healthy?

I'm 5'6-5'7 (idk but I'm taller than my mom and she's 5'5). Am 125 pounds. I was having all of these stomach issues, especially while on Keto (constipation, diarrhea, cramps, nausea, gas, indigestion, burping liquid, etc). I tried changing up my diet so see if it was food allergies. After weeks of experimenting with different food types which in turn changed my macros and taking notes, I found out the culprit. Fats! And these symptoms usually occur shortly after eating. Example: stomach cramps every time I eat peanut butter sandwich (but not after a tuna sandwich). Stomach ache whenever I eat ice cream unless lowfat or fat free. Cramps after using olive oil or butter. Burping up after egg yolks. Carbs and/or protein alone don't do this. I went off of Keto and had less digestive issues however still had some on a moderate fat intake so I lowered it to 20% of my calories (35-40 grams). Still getting the occasional cramps, gas, burping liquid, bowel changes, etc though (just less frequent and less severe now). But I want it gone. What's the absolute lowest I can lower my fat intake and still be in good health? I eat 1600-2000 calories a day, depending on the activity. My body hates fats, even the good kind!