I lived on three foods for over 5 years. Yes, FODMAP is tough, but it was heaven for me when I could add more foods. So, yes, you will get to the point where you can have the garlic and onions again. I would say start very slow. (I literally had to start with pinky sized fingertips when my body was ready.) Listen to your body, be patient and most importantly DON'T GIVE UP!