My Mother In Law Has Chrones Disease. She Had A

my mother in law has chrones disease. She had a second resection that her surgeon said she should be in pretty good shape for a while with regard to her colon. That was only 3 months ago. She has been sick the last month almost daily. When she eats she throws up pretty soon after and has the runs as well. She was reevaluated by her chrones Dr. who said that from the Chrones perspective she is fine. She has had a quadruple by pass about 5 years ago, she is on Plavix and has a pace maker. She can't even make it through the stress test due to sickness. What should we be looking for? What are some possible reasons she is doing this. Also, she does NOT appear to be loosing weight. What could we be dealing with here??