A man wants to be with the one with whom he feels free to be himself

A man wants to be with the one with whom he feels free to be himself. And you can't fake it. You either let him be free or not. He senses when it's not sincere, when it might change, say, after marriage. How do you prevent him from feeling free? When you want to push the relationship too much, when you think time is running out, that you need to have children, when you can't be alone. All of this hinders the relationship from developing naturally.