Have I erred in my treatment of my wife by being unable to occupy her free time, and how can I address the issue of her idleness? And what am I permitted to see of my fiancée during the engagement period before consummation, and is it permissible for me to kiss and embrace her?

The problem is clearly the wife's emptiness after leaving work, which makes her regretful and think about returning. The ideal solution is to hasten the consummation of the marriage and live together, as there is tranquility and peace in that. Alternatively, you could allow her to pursue a permissible job with শরعي (Shari'i) controls, or complete studies that do not require constant outings. As for the second question, after the marriage contract, both spouses become lawful to each other, and it is permissible for them to enjoy each other.