Hey man, you took great care of her. She enjoyed every minute being with you. Cherish those memories.
From my own experience, it never stops hurting. It may hurt less in the future, but the pain of not meeting our little feathered friends still stings. It will, however, be dwarfed by the lovely memories and experiences that were shared between Sunny and you.
A burial is a good start to getting some form of closure. You can also plant a tree in Sunny's memory, or adopt other birds in need of a loving caregiver and a safe home. Honor Sunny's memory in any way you can. I also suggest writing a journal/diary detailing Sunny's life. It will evoke pain(my little friends passed away in July and it still hurts writing about them), but will also bring up joy and a lot of happy memories.