How about.. smoothie/juices/soups? Maybe you don't feel like chewing out of exhaustion. Drinking can help until you want to munch again.

How about - making some healthy sauces to spice up regular meals? A simple rice is not simple anymore with the right sauce :)

Also.. bites - don't make big sandwiches that you feel are long and tiring to eat - make many mini-sandwiches to snack on when you feel like - it just feels different :P

Mint relaxes - might help (can be used as spice or in smoothies)

Coffee helps to sense individual aromas and to taste better.
Some teas may open up appetite.

Anything slightly sour like fruits or lemon in my water tend to help me find my appetite - might help you as well.

Fresh air - go out (walk if mobile) or open the window - it helps.

Laugh - seriously - finding something funny to laugh about does improve appetite :D

If you have access to some farms that respect the food (no pesticides, no fake stuff fed to animals.. you may find that non-treated food smells and tastes better. Of course, there is a risk of finding a bug in an apple or a peach that has not been sprayed... but the aroma and taste of the wild grown fruits kissed by the sun is worth the occasional "discovery"., don't you think? If you are not mobile, maybe some family member or friend can look around for you.

Hope you find your appetite soon! :)