Can't really offer any advice about Liver Flushes as I've never personally had one done, but I have had colonic hydrotherapy before. The center I went to told me that you should do 12 within a year I think. They start you out just using water, and then around the 4th or 5th treatment they start to use a mix of water and coffee (like a coffee enema I guess). I never got as far as the coffee. I stopped going after my 4th treatment.
After each of my 4 treatments I did feel a lot lighter, like a heavy weight was lifted out of my colon, and I did feel better in a sense, but it didn't help my bad breath at all (because my bad breath had nothing to do with having a backed up colon). But if your bad breath is caused by a backed up colon then maybe the colonics would help.
Oh yeah, about the liver, I have taken pharmaceutical grade milk thistle before several years back (it was from Germany I believe). I heard it is supposed to be really good for the liver which is why I took it because I thought all the drinking I did in my younger years probably did some liver damage. Seems like the supplement you're taking now has Milk Thistle in it so looks like you're on the right track.