I am so sorry you have the flu - it can be debilitating. You will get through this stage with the feeling unwell and all the feeding and it's nearly spring.... I know I've sometimes felt I needed a week off from feeding the pets and we only have two hamsters! I actually do get a few days off a couple of times a year when visiting family and leave my OH to do the feeding
When we went on holiday we have a trusted pet sitter to do the feeding.
If it's feeling too much at the moment, is there a pet sitter who could come in for a week to take over maybe? Just to give you a break?
I am fascinated by the care of the baby birds - that is a special thing to do and I have learned something from you there. I have rescued the odd bird in the past but never knew what to feed them (as children we were taught to give them bread soaked in warm milk and they usually died!). The hardest thing was keeping them in a nest/from escaping - I assume you have a bird cage?
The Dove sounds like they are your pet! You hand reared him/her and he/she will probably think of you as its parents! Will you keep it as a pet or let it go? I guess birds do fly the nest!