Although he's born in a flexible Mutable Sign, his planet, the quick and clever Mercury, will not allow his freedom to be compromised in this way.
In fact, he may bring more changes into your life than you bring to his!
Together you'll make a terrific financial team. It can quickly become a rut that causes his Mercurial mind and youthfulness to atrophy.
Many of his complaints come from the lack of variety in his life; don't add to it.
He may occasionally be a little jealous of the attention you get from others, but he'll never be jealous of your ambitions.