It's difficult to imagine, not being sexually involved with someone with whom you share bondage sessions. In my mind, they go hand-in-hand, and the bondage is simply one of many ways to enhance/heighten the sexual experience; and hopefully, that person with whom you are engaging with, in bondage, is someone you love and actually want to invest your time and your heart with, and he, with you. It's not just entertainment, but an extremely bonding experience, with that person. Bondage is an extremely intimate thing, and requires a lot of trust, on both parts, and definitely open communication, and there has to be a mutual understanding of what the limits/expectations are, and the lines should not be crossed - ever.
I also believe that it makes no sense to spend the rest of your life with someone, and not know, for sure, whether or not you are sexually. intellectually, and yes, spiritually compatible, then have to be stuck with that person, exclusively, for the rest of your life, because you didn't take the trouble to find out, beyond a reasonable doubt, by living with that person, for at least a year, first. That's when you begin to truly know someone - warts and all. You can date a person, five days a week; but you simply will not truly know them until you live under the same roof. Of course, that's my opinion, and opinions vary greatly. I think it's idealistic to believe that everything will just magically fall into place, once you marry someone.
I wish you the best of luck with this man, and I hope he loves you enough to be open with you about his true feelings, sexual, and otherwise, and I hope you can come to an understanding about works for both of you, rather than holding..or withholding things from you, just to get his "happy ending". That sounds like very passive-aggressive behavior, and you deserve better.
That's just my opinion, for what it's worth.