Based on conjecture… I think you’re feeling trapped.
Trapped by the commitments in your life, with the strongest commitment being your marriage.
The house on the water symbolizes that you’ve no where to run.
The families symbolize the people whom you’re committed to.
This part is going to be stretching it… But with your wife, you feel as if she’s the one you would be happy to ‘run away’ with, but wouldn’t accept it.
I’m no therapist, but I might recommend going to one, especially if you’re dying in your dreams often, as that’s not typically a good sign.