Do these sentences sound unnatural to you?
I need some expressions about metaphor: "HAPPINESS IS A BRITTLE OBJECT." in English. However, since it's not my native language, it's hard for me to found them. I write some here but I'm not sure whether it's natural or not. I'm looking for help form you. If you know any popular example in your language. Please, let me know.

1. Their happiness are so fragile.
2. He have to handle happiness with care.
3. Happiness shattered.
4. Happiness broke.
5. Happiness goes into pieces.
6. Happiness snapped.
7. Break happiness

Question

Do these sentences sound unnatural to you?
I need some expressions about metaphor: "HAPPINESS IS A BRITTLE OBJECT." in English. However, since it's not my native language, it's hard for me to found them. I write some here but I'm not sure whether it's natural or not. I'm looking for help form you. If you know any popular example in your language. Please, let me know.

1. Their happiness are so fragile.
2. He have to handle happiness with care.
3. Happiness shattered.
4. Happiness broke.
5. Happiness goes into pieces.
6. Happiness snapped.
7. Break happiness

Answer

"Happiness is fragile." would be a good one. There isn't a standard expression for this that I can think of.

Of your options, " You have to handle happiness with care." is the only one that might work, but it's longer and not as clear in its meaning as my suggestion.