Hello mate,
My case is just the opposite. We started on this only a few months ago, and since we started I never participated and watched them.
My GF is very reluctant to have me there with her.
In my case I think I'd enjoy watching them, but maybe just once for curiosity.
Since my GF is fully open to share every minor detail with me, I enjoy extremely the moment of arriving home after their encounters. We stay In bed and I jerk while she explain me every single orgasm she had with him. For me this is fucking awesome...