I'd like to make some suggestions in regard to wife's condition.
The diagnosis of IBS is often a blanket diagnosis for an underlying problem that hasn't been detected, yet. I realize that you are desperate and seeking answers for your wife's condition, but you need to take one step at a time and evaluate information. In your journey in seeking answers it would be wise for you to do a lot of research before embarking on a protocol and avoid jumping around in trying many things (because it could make things worse) without having an understanding of what you're dealing with or HOW the protocol may affect that condition. Once you find something that may make sense to you, by all means, ask a lot of questions so that you can learn more information. Then, try something. :)
I'd also like to suggest, if you plan on using medications it would be wise to read whatever you can about those meds. Question everything, even your doctor's advice. Read all material on the Pros/Cons (from several sources) and see if it can really work for your wife's condition. Personally, I think natural methods are better, but do what is right.
Olive oil may not be the problem, at all. The breathing problems that your wife is now experiencing could be a result of "disturbing" hidden bacteria or possibly die-off from the meds and liver flush. There could be something else involved with the breathing too that should be considered. Dealing with illnesses is a complicated issue because many of us discovered that there is MORE going on than we had initial thought or was diagnosed with. For instance, I've been dealing with parasites, bacteria and mold in the lungs - initially, I was attacking an intestinal parasite problem - all 3 co-factors have affected me greatly. The process is slow because I need to be careful in dealing with these pathogens [it would be nice if it were just a worm problem but this isn't the case, unfortunately].
If you do proper research, as suggested, you may find a post where someone provided information that stomach bugs can affect the lungs/heart [this may NOT be the problem, but it is something to look into deeper]. Your wife may have done a little too much and it might be a good idea to pull back a little and allow the body to get its bearings. Depending on co-factors involved it is not always a good idea to hit things hard, sometimes it is best to go at it slowly. Bacteria can act like a parasite and it can "attack" or fight back like other parasites. I can tell you from first-hand experience that fighting parasites is not as easy as it sounds, especially when they want to attack for disturbing their comfortable home. Certain procedures need to be followed to avoid problems. As you and your wife are doing research, it would be a good idea to continue with probiotics and go on an alkaline diet - until you find a protocol that you are comfortable with - there is information here that you can look in to, as well as, other places on CZ.
There are MANY Forums within CZ and many people are generous in giving direction and sharing what worked for them. Unfortunately, this Forum isn't designed for a lot of cleansing protocols and limited on "advice" in terms of trying things [this Forum is designed this way on purpose]. However, we provide EXCELLENT information on herbal studies, scientific studies, etc. to help you for a better understanding in your research. In your post below I found some information for you to get started in your research; I also see that 70428 has provided some information too. If you need help in research - people are willing to help with providing links and reading material - it is what we do best, here.
Again, I can't stress enough for you to read and ask many questions before jumping into a protocol just because someone suggested it and it worked for them (not everything works the same for people). Proper research can make a difference between success or creating a disastrous problem. If you are uncomfortable and still unsure what to do, a qualified ND practitioner might be helpful to you with proper assistance with a natural approach.
As mentioned before, there are no Medical Doctors on this Forum but we are more than willing to point you in a good direction for better health with research material. :)