First of all, I have two children and love them each very differently. However, they each KNOW about the other one. Now, granted, they don't get the right to consent to whether or not they have a sibling, but they've never been lied to that they are the only one. Not to mention, love and feelings for children are VERY different than the emotions one feels for a lover.
Are your partners each aware that there is another partner fulfilling needs that he can't? Then more power to you, and enjoy them all you can. If you found that either of them has another relationship would that be okay with you? If your real life relationship found out about your bdsm needs and wanted to fulfill those needs would you give up the online one?
Also, if you can't expect the partner that you are with in real life to be open to finding out who you are inside then what are you doing with them? There are portions of Ragoczy's personality and desires that I haven't an interest in and am more than happy to have him engage in on his own or with others, like kayaking. But I KNOW his personality inside and out and I ACCEPT his personality and wants and needs as part of him. Without that, what we have would not be what it is.
-kitten