No, I don't find it disturbing.
I find it different, and unusual but not disturbing.
What is disturbing is that many woman on here say it is abusive, that they are subjecting their kids to their shagging, that it's disgusting.
There are many different people in this world and we don't all want the same things. Just because you wouldn't do this, doesn't make it wrong. Have any of your seen Sister Wives? A man has four wives, and 18+ children, and they are all pretty well balanced because it is is the norm for them. The mothers introduce themselves as parents of those they haven't birthed, because they have had a huge part in raising them.
Most of the older kids have decided not to follow in their parents footsteps, and yes, the families have faced some battles. But it is not akin to child abuse, and no one sees any affection from the adults over and above a simple kiss.
OP, if you are still here...I knew how this would turn out before even reading the responses. For all the MN contains mostly forward thinking people, a lot do not like the breaks from what they perceive as the norm, so will many will never accept that the three of you can be happy. As long as you are all, that is all that matters.
Most who have asked questions/left judgemental responses have helped many a woman stuck in abusive relationships with controlling men and for some reason see this type of relationship as nothing but controlling.
Others, it is clear have not read your responses. Don't feel obliged to come back, because you will not change their minds. Just be happy, and when you are no longer happy, be strong enough to change it.