As I said above, there are enormous similarities between the principles behind BDSM and Biblical marriage, because God created our desires and this movement has been built as people rediscover these principles for themselves. There are distortions, but that doesn't change the fundamental similarities. To describe a Christian marriage in BDSM terms:
- Your husband is your Dom / Master.
- Your decision to marry was you agreeing to your Contract (similar to a M/s contract). However, the terms were not written by you, and cannot be renegotiated. The terms were written by God - in the Bible. So the Bible contains your Contract. Read it to find out what the terms are, and follow them as you discover them.
- The single most important clause in the Contract is that you are fully submitted to your Dom, and cannot go to another Dom. To be sexual with another man is completely forbidden (the Bible labels this "adultery"). Because it's so serious, in order to prevent this, to submit to another in any way or desire to be sexual with another is also forbidden. You are to be 100% devoted to one Dom / Master in every aspect of your life.
- Whether the sexual relationship between you and your husband / Dom is "vanilla" or "kinky" is up to you. There are almost no rules. Have fun!
- Whether your Dom has just you, or takes another as well, is up to him.
See how similar it is? So it can certainly work in a Godly way.
Keep doing whatever you're enjoying with your husband. It's probably fine. God designed you to enjoy it. And if there's anything you're doing that He wouldn't want you to do, He can show you this through the Bible or otherwise. Don't worry about this.
It's far more important for you to be considering why you describe yourself as an "on the fence" Christian, and thinking about what it would mean to be fully, 100% devoted to serving God.
Because although your husband is your Master, God is his Master. So God is your Master's Master. To put it in business terms, your husband is the branch manager, but God is the business owner. If you should be devoted to your husband, should you not be even more devoted to God? If you hear your husband's instructions and follow them in your life, is it not even more important to find out God's instructions and work out how He would have you both live?
You know how to submit to a man. You need to learn how to submit to God.