Ambivalence is a state of having simultaneous conflicting reactions, beliefs, or feelings towards some object. Stated another way, ambivalence is the experience of having an attitude towards someone or something that contains both positively and negatively valenced components. The term also refers to situations where "mixed feelings" of a more general sort are experienced, or where a person experiences uncertainty or indecisiveness.

Explicit ambivalence may or may not be experienced as psychologically unpleasant when the positive and negative aspects of a subject are both present in a person's mind at the same time. Psychologically uncomfortable ambivalence, also known as cognitive dissonance, can lead to avoidance, procrastination, or to deliberate attempts to resolve the ambivalence. People experience the greatest discomfort from their ambivalence at the time when the situation requires a decision to be made.

Ambivalence is a complex concept, but is also a relatively simple one that could be explained quite easily by the following example: Someone goes to an Italian restaurant but struggles with the menu and can’t decide whether to order pasta or pizza. This type of ambivalence is common and can also be understood as indecisiveness.

More Info: en.wikipedia.org