I don't think romantic love is the same as finding a worthy partner to start a family and maintain a long-term and stable relationship.
Of course it's the same. Without sexual intercourse there is no pair bonding
One is mainly passionate and ephemeral, while the other takes much trust, communication and strength to go through obstacles along the way.
Do you know any marriage that hasn't involved sex and attachment?
As for sexuality, it is part of a relationship with a partner, but it is only a part and not as important compared to the others.
I wonder how many marriages survive without sex, or at least some display of affection which is another way of showing attachment.
I find it hard to see how having a husband and children would lead to Nibbana? It seems to me that a family entails attachment, which is anathema to Nibbana