Luckily, I don't have a nut allergy, so I've added a lot of nuts to my diet, which has reduced my protein costs quite a bit. I also switched from red meat to lean chicken and I've purchased that in bulk and then eaten it sparingly. Instead of fresh vegetables, I've bought frozen veggies in bulk and those should last me a really long time.
One thing that makes me facepalm is that I didn't even realize that most fruits could be stored for weeks safely if kept in the fridge. I've been throwing away so much fresh fruit up until now. Oh, well. Better late than never, I suppose.