@tormented728,
When I first started reading I was thinking jeepers this sounds a bit like me and my current husband....my initial thought was as long as he earns enough to support himself (you could always take over the finances as you seem better at it)....but then you said you were in your 60s - this does change things.
Question - what does he have saved or plans for retirement? Does he have a 401K, IRA, pension? How and when does he plan to retire and how does he plan to support his retirement? And you as well? That to me is the fearful part. If he has nothing for retirement then would this deplete your retirement or cause you to work longer than you plan?
I think the other things you could work out. It would more be an agreement on who/how much you each share towards expenses that you would both be comfortable with. I don't necessarily think it needs to be a 50% 50% split depending on the situation - do you own the house you are living in? If he pays rent - it might not be a 50/50 split but on your side he is paying toward the equity of your home and you also benefit as you are now paying less than you did before so you can save more as well. I think it is more finding the right amount that benefits both of you - and so you don't feel he is taking any sort of financial advantage of you.
But before anything you need to have a plan for retirement and to ensure you can retire as you want and when you want.