John Wain's book, The Living World of Shakespeare: a Playgoer's Guide, is full of quotable moments, but like all such books, remembering where the moments are without making a note in the pressure of reading is a bit of a task.
Anyway, here from page 39 of Papermac edition:
...the dispossed king is a powerful symbol, for deep down every man thinks of himself as a dispossessed king.
and from page 75:
...the deep heart of courtship...is of course, self-knowledge. The reason why young people so frequently select the wrong partner is because they hold mistaken views about their own characters. The first essential for a lasting love of someone else is a sound assessment of one's own identity. Only when we see clearly what we have to give, and what we need from others, can be begin to be happy a deux.
I believe what Wain is saying here, but I suspect that for most of us this self-knowledge only comes after we've lived with someone for a long time, rather than during a period of courtship, where the passion of love tends to blur the edges of anything the other person actually is.