Complex sentence: Edward (who seems to have preferred women older than himself) was more interested in her person than her property, and she insisted on marriage, so Edward married her in secret (or, at least, made a legally binding contract to do so).
Split into simpler sentences: Edward (who seems to have preferred women older than himself) was more interested in her person than her property, and she is said to have insisted on marriage. Edward is alleged to have married her in secret (or, at least, made a legally binding contract to do so).