I killed my finches

I was so stupid! I killed my darling finches. We had built a big flight cage for them that nestled up against their store-bought cage. A couple days ago, I shooed them into the regular cage so I could service the flight cage. Every day since I've checked the food and water in the flight cage but never once noticed that I hadn't re-opened the door between the cages. Every day I went in there, and they thought that this time I'd take care of them, but I never did. I failed them. They starved and/or died of dehydration within sight and smell of both. I feel so terrible. I loved those finches. I hate owners who abuse or don't care for their pets, and now I have become one.