Congrats but the best way to change her mind is to show her how you and your body have changed. Also Primal isn't just about how we eat but how we feel, our mindset and attitude. If she can see a change in you then she'll be more open to it. Also cook the food for her and do it primally so she doesn't have a choice but to eat better. Once we create a strong habit its hard to break.
Also try almond milk as a milk substitute. We don't drink cow milk anymore after I told my wife that its kinda weird that we are the only species who drinks milk from another species on a consisten basis. We all know the hormones and antibiotics they are forced to injest so why would even bother with it?
Today is a new day. You will get out of it just what you put into it. If you have made mistakes, there is always another chance for you. And supposing you have tried and failed again and again, you may have a fresh start any moment you choose, for this thing we call 'Failure' is not the falling down, but the staying down.