Is it permissible for a husband who loves another woman and wishes to marry her to take her as a second wife, knowing that he is already married and has limited financial means, in order to achieve his psychological stability, or would his second marriage be considered an injustice to his first wife?

If you find yourself capable of bearing the costs and provisions of a second marriage, and of dealing justly between the two wives in terms of sustenance and cohabitation, then there is no impediment to marriage. However, if you do not find yourself capable of doing so, then it is better to abstain, so that you do not neglect the obligatory rights, thereby incurring sin. It is recommended to perform Istikhara (prayer for guidance) and consult those with sound judgment.