How do you explain what a hopeless romantic is?

A hopeless romantic is a person who holds sentimental and idealistic views on love, especially in spite of experience, evidence, or exhortations otherwise.

Why are romantics hopeless?

You have unrealistic expectations on every romantic situation. Hopeless romantics always find themselves in a room full of disappointments because they let their expectations take over reality. If life and love were to take its course on our own preferences, it would be a boring and predictable life.

What is the opposite of a hopeless romantic?

The opposite of a hopeless romantic is a realist.