Should one withdraw from marrying a respectable girl who works in a mixed environment and sometimes tolerates talking to her male colleagues, especially given intense jealousy and a desire for her to stop this leniency, despite repeated Istikhara prayers indicating her suitability?

We have previously explained the importance of considering religiosity and character when choosing a wife. If your description of the woman as "respectable" means that she is religious, observant of her religious obligations, and avoids prohibited acts, then there is no objection to marrying her, with the possibility of stipulating that she leave her work in a mixed-gender environment. The marriage to her is valid. A woman's religiosity is not impugned if she speaks with her male colleagues at work without being submissive, alluring, or provocative. If Istikhara (prayer for guidance) is performed according to its correct principles, its outcome will be good. One of its principles is that the Muslim should not have a pre-existing inclination towards either of the two options before performing Istikhara.