The therapist's feeling of respect and affection for the client that exists without any strings attached, no matter what the client may do or say, is called

Unconditional positive regard

Explanation:Unconditional positive regard is an expression of feeling  which is usually referred in the case that focuses on the client therapy mostly. It is the emotion that describes about a person having no expectation in return toward their feeling and being supportive and respectful towards the client.

The therapist is also displaying this emotion from his side towards the client irrespective of the client's emotion .