Step 1: Understanding the Context:
The sentence asks about the likelihood of being unhappy, and we need to select the correct word that fits in the context of uncertainty and negativity.
Step 2: Analyzing the Options:
- Ever: This generally refers to any time in the past or future but does not fit the context of the sentence asking about the likelihood of being unhappy.
- Forever: This implies an unending duration, which doesn’t quite fit the context of being unhappy.
- Never: This is the correct choice. "Never" fits the context, as it means that the person expects not to be unhappy at any time.
- Not: This is incomplete and doesn't fit the sentence grammatically.
Step 3: Conclusion:
The correct word is never, as it fits the context of the sentence.