There are two extremes to be avoided. Don't be an abusive and aggressive husband who says no for the sake of saying no. And don't be a disengaged, passive husband who can’t say no at all.
What I have seen is that you cherish this woman. What I have seen is that you are willing to point her toward Christ and his Word. What I have seen is that your love is sacrificial and stable. I’m confident you are ready to do this, and do it well.
The boundaries we create should not be about what annoys us, but about what blesses those we are called to serve. Wear your authority lightly and take your responsibility seriously.