Severe abdominal pain everyday

Looking for any help. My wife age 60 has had severe abdominal pain for a couple of years. It has increased to everyday. It lasts from several hours to all day. Been working with GI Doctor with no diagnosis as of yet. She bloats & vomits quite a lot. Mostly yellowish which indicates bile. Seems to be a lot of gas in stomach also. Constantly working out burps which seems to ease pain. Will also mention that bowel movements are infrequent & painful. Cycle of ER visits have increased to couple times a week. But that only helps temporarily. All prescribed medicines don’t seem to help. Tests are always negative. Did both upper & lower GI scopes with no findings. She has been through ringer with still no diagnosis. She is tired & has no quality of life. Any help is most appreciated.