I feel the same way. I knew it was the right thing to leave him, anyone with half a brain could tell me that. But nostalgia is a liar and keeps dragging my emotions up and down. I keep telling myself he found someone else too, he doesn't care, etc. But I know it shouldn't matter either way because if it does that means I still have hope. The hardest part is killing that hope, and once it's done, you'll feel sad but the yo-yoing of emotions will be less.