The first thing that comes to my mind when I think of a food that is bitter but sweet is dark chocolate or bittersweet chocolate. Dark chocolate is made by not adding milk to it and contains fat, sugar, and cacao. It has that bitter taste to it yet is sweet at the same time. It is also a healthier form of chocolate. Dark chocolate contains anti oxidants which are very good for you.
Chocolate has always been a favorite gift that men give to women so it is most definitely an expression of love.
Well in order to make good wine some grapes may need to be sour.
Another thing is lemonade- both bitter and sweet and delicious, mixed together and blending perfectly, sort of like when you love someone.
I would end up saying that one of the most delicious bitter sweet things in life are Life Savers candies. If you compare them to love, they are sweet, sour, they melt, and they make you feel young again.
It could help ;)
A perfect example of something that is delicious because it is bitter and sweet at the same time would be Lemon Pancakes! These are a very desirable dessert, and the light sugary but sour fruity taste can certainly be a flavor that people love! For example, you have the rich but crispy texture of the egg batter, the sharp citrus bitter tang of the lemon juice and of course a light sprinkling of fine caster sugar to make the zesty taste palatable and sweet and the batter crunchy. Oftentimes too, experiences are heightened by distance or separation ('parting is such sweet sorrow') as in the saying 'absence makes the heart grow fonder.' However, it's also worth remembering 'out of sight is out of mind.'