The one word for a person who has already had a bitter experience is "jaded." This term describes someone who has become weary or disillusioned, often due to repeated negative experiences, leading to a loss of enthusiasm or trust.
"The idealism of youth can be a bit wearying to those who have learned better from bitter experience."
a hateful/mean/unpleasant person
Resentful.
The opposite word of bitter is sweet, and the opposite word of sour is sweet.
it's "mapait"
The word bitter is an adjective (and in another context a noun). The adverb form is bitterly.
something that causes you to have a bitter or highly unpleasant experience. Gall and wormwood are plants that were often referred to for their bitter taste in the Bible and Shakespeare. (The modern word gall now refers to bile, rather than a plant.)
Misbitter - to make something bitter or resentful.
kaduvaa
sweet
From the word alumen meaning substance having a stringent or bitter taste
"You are the worst person I have ever known because you're as sour as a molding lemon!"