How can one reconcile his desire to marry a second woman who pleases his heart with pleasing his mother who opposes this marriage for social and material reasons, especially given his eagerness to honor her?

Obeying one's mother takes precedence over marrying a specific woman if her prohibition is for an acceptable reason. One should try to persuade the mother kindly and involve intermediaries to help with this. Disobeying her is not permissible if her refusal is justified. If her prohibition has no valid reason, then obeying her and pleasing her is still paramount, unless it leads to harm or disobedience. Illicit relationships with foreign women must be avoided.