20 years ago is a long time..
make sure you are not holding on to error thinking..
my mom had cancer when I was 1 year old.. I lived with that all my life.. MOM died at 91 from yet another cancer..
when I was 16 I was so worried that mom might get sick again that I threw up all over the sidewalk..
mom had colon cancer 10 years earlier.. she had surgery and all that could go wrong, yet she survived, and then went and lived her life until another cancer took her life strength. Yet to the end she lived with a happiness I can never match.. I am trying do do the same.. so mom could have died suddenly from old age, overnight, or give us all a chance to keep her for 8 month after the final cancer diagnosis.. She must have known after the treatment that she was not coming back as she did before, yet she never talked about it, other then on the last day when she told sis had to go away for the day : ALL is well don't worry".. by evening mom was gone..
Would I wish I never heared the word cancer, did not see my grandfather die from it, nor see others in my family having to have this or that removed starting at age 20 and their father dying at age 60 despite that he lived a healthy life and never had a day being sick.. My husband died over night while working.. I have no idea what is worse nor better..
BUT i am saying this not for the answer to your question, just to tell you that some things in life have no answers. Maybe mom did not want to hear the facts, maybe she had all the reassurance that she needed, maybe she past a gall stone, or some other thing popped - like cyst or some such - unless you get her medical records or find her doctor, you will not know and now the times have changed, we can find things easier and better, so why fret over olden days?? (my mom threw scar tissue at on age when that does not happen - so you see one never knows..
WHAT are they doing for her TODAY??
As for your own intestines. there is no doubt in my mind that Mom had something to do with it either not feeding you the foods you should have.not her fault! or her emotions made you insecure causing you problems - for you. Neither you or she are gaily.. life just happens that way.. .. I am sorry for either of your situations.. but YOU TAKING CARE of YOU is most important and this board will be here for you and so will the food plan work for you better then anything else I know of..
STAY strong and keep bad thinking away.. get in front of a mirror and say out loud : I like myself! and you might even say: I like my MOM.. Say it until we can hear it here.. and every fiber in your body will feel it too. as for history, it has its place, but answers are hard to chase and often they don't matter all that much.
I learned a long time ago that it always pays to ask: What matters in 5 years???.. and often the situation is long resolved by then and it does not matter at all..
I am sorry not to be of more help here..