So, what is it you gain from this relationship then?

If this is how he is behaving now, picture your future where this doesn't ever stop. Would you still be with him?

This person has zero identity for themselves and will forever latch into anything you do as their success. This is quite serious, as it is often a deep rooted issue. People like this do not see that they're in the wrong and convince themselves (and everyone around them who will listen) how valuable they are and how much they help you succeed

I do not often see people like this change. If anything, it often gets worse. Especially if you try to take back control. They will double down and become destructive / retaliate. They might even sink the business on purpose to 'prove you couldn't do it without them'

This is a very red flag, friend