You're doing the right thing by sticking with Heather's diet. Try your best to give it a chance to work, and then go from there. It's important to stick with one method for a period of time, and not confuse the issue with trying too many new and different things at one time. How will you know what is working?
I would just keep main dairy sources out of my diet. Milk, cheese, yogurt, butter, cream, half/half, ice-cream, etc. Minute amounts might be unavoidable, so I would not stress about that.