I have just decided on a whim that I no longer want to support the dairy industry and cut it out of my diet cold turkey. I've already trialed a run and I felt great but it was so difficult. Never realized how much dairy was in my diet in basically everything I ate and it wasn't long before I ran out of things to eat that didn't contain it. Even subjected myself to eating cereal with water which was extremely unpleasant. It's been hard but I know you're the community to ask for help because you've probably went through this sort of thing before.
When I say substitutions I'm referring to the nutrients, convenience, and cost. There's no point in subbing something out if it's going to take 2 hours to prepare, cost 10x as much to make, or is as nutritious as cardboard. Believe me when I say I have run into all three, especially when it comes to 'health' foods which are essentially overpriced candy designed for false consciousness.