It takes effort for long term marriages to keep Eros love strong. But when Agape love is very strong, it can be enough for some of us, so the effort to maintain Eros love often falls away.
Does this help explain my 'lack of passion' comment? Eros had dwindled but with deep Agape love we were okay with it. Until... the unthinkable happened, and an affair was born to satisfy the desire for Eros love. So it's really NOT okay to ignore Eros love either. It definitely needs to be present in a healthy marriage.
This is a pretty simplistic way of explaining and others might disagree. I believe that MLC also defies this explanation. I think it was a factor in my marriage, but wouldn't go so far as to say it caused the MLC or could have prevented it.
I will respectfully disagree and say in a healthy relationship based on trust, years of commitment, respect, and as you say Agape love Eros love flows directly from that deep source rather than the shallow chemical "attraction." And that mature healthy psyches recognize that difference and strength of this over the "rush" fake excitement once you are no longer 16 years old.
But that is my view. I always loved my wife and was attracted only to her because I loved her, and didn't have to work at Eros love. And when a new person triggered a momentary attraction it simply faded away when compared to what we had.
And this is a big part of the tragedy of what people in MLC completely lose.
