I did answer your question Alice, but perhaps not in the manner you wanted. I stated:
“The primary provisions are food, clothing, and shelter. He is also supposed to provide his wives with their conjugal rights as well.”
I assumed that your question was a rhetorical question in that it attempted to answer itself, but I left a brief answer in any event. Your primary concern presented was of a sexual nature and therefore I spent most of my reply addressing that.
From a biblical perspective as long as he can provide food, clothing, and shelter, as well as perform sexually (to any extent) there are no biblical texts I am aware of that indicate a man should not take a wife or an additional wife as he sees fit. Most certainly the better he can provide for her and the better he can perform, the better the relationship should be between them.
My mother lived with my step father for 20 years while he was unable to perform at all…not one bit. Due to medical conditions he was unable to attempt to perform his conjugal obligations even with the assistance of other means that may have made it possible. He had had numerous heart attacks and strokes; it simply was not an option for him to even try. My mother still treated him like a king, and they loved each other deeply, setting an incredible example for all that knew them.
If we begin to define points of qualification, adding our own rules and regulations based on our interpretations and opinions, then we become nothing more than Biblical Marriage Pharisees. Maybe I should just sit back and wait for the final edition of the 613 Laws of Biblical Marriage final edition to be published. (sorry...sometimes I do get a bit sarcastic...no insult intended Alice)
From my perspective it seems that he needs some Biblical Marriage buddies to help him realize the things he can do to maintain and improve the relationship he has with you. You love him, and quite frankly I think you would bless him tremendously by becoming his wife. It is simply a matter of him understanding your needs and being willing to meet them. If he is unwilling or unable to do that you may never be happy and it may just make matters worse for both of you.