All perfect praise be to Allah, The Lord of the worlds. I testify that there is none worthy of worship except Allah and that Muhammad, sallallahu ‘alayhi wa sallam, is His slave and Messenger.
Happiness and sadness and love and hatred are matters of the heart that are beyond the person's control, so he will not be held accountable for them. It is possible that this feeling is not jealousy on your part. It is natural that the wronged person rejoices in his heart with the harm that may afflict the one who wronged and harmed him, so he is not required to feel sad for them. Rather, the Islamic Sharia makes it permissible for the wronged person to do what is greater than harboring such feelings, which is to seek retribution against the person who wronged him, within the limits set by the Sharia; by retaliating with the same as what he was wronged with, not more; and the like. Allah, The Exalted, says (what means): {And if you punish (an enemy, O believers), punish with an equivalent of that with which you were harmed. But if you are patient - it is better for those who are patient.} [Quran 16:126]
Hence, since a person has no control over the matters of the heart, then asking about the feelings and thoughts that you should experience when you see the people who wronged you has no answer. Our advice to you is to concentrate your efforts on what benefits you in this worldly life and the Hereafter.
Allah knows best.