How Should Severe Gastric Problems With Diet Restrictions, Migraines, Weakness Be Treated?

my mother, aged 50 has severe gastric problems, she has some intestine inflaamation problem and has been advised to avoid lot of things in diet like dals, besan etc. now she cannot eat practically so many varieties of fruits and raw vegetables and many other things which even if she tastes she gets severe migraine attacks, although she used to get migraine attacks earlier also but now it is very often and as noted mainly by stress or by eating any of the things which she is not suppossed to eat. she also has lot of general weakness in body and pain in palms of hands, she has got checked for gout and rheumatoid arthritis and has tested negative. two years back, she had got her routine ultrasound, blood tests done which revealed inflammation in the intestines. plss suggest, her prob is a continuos one affected by stress also