I wish I ____ him, but I don't.

The correct sentence is "I wish I liked him, but I don't."

In English, when expressing a wish about the present or a regret about a present situation, the verb in the wish clause is typically in the past simple tense. This usage does not actually refer to the past but is a form of the subjunctive mood, which is used for hypothetical or unreal situations in the present.

• "a liking" is not grammatically correct in this context. "Liking" is a noun or gerund, but the structure of the sentence requires a verb in a suitable tense.

• "like" is the present tense form of the verb, but when expressing wishes about the present, we use the past tense form, even though we are talking about the present or future.

• "was liking" is the past continuous tense, which is not typically used in wish clauses. Wish clauses about the present usually use the simple past.

• "liked" is the simple past tense of "like," which is the correct form to use in this sentence. The sentence expresses a hypothetical or unreal situation in the present: the speaker does not like him, but they wish the situation were different.

Therefore, "I wish I liked him, but I don't." is the correct and grammatically appropriate choice.