What is the ruling on the feeling of uneasiness when seeing someone you admire with others, even if she doesn't want him as a life partner and wishes him well?

Mere admiration and respect are harmless, unless they lead to something forbidden like looking, touching, or private seclusion (khalwa). Her discomfort upon seeing him with others, if due to jealousy, is a dangerous sign of infatuation. However, if it is because she considers him above meeting foreign women, then it is a good sign. She must fear Allah, lower her gaze from non-mahram men, avoid mixing with them, and occupy her thoughts and time with what is beneficial.