It is great that you feel such joy in your relationship. The problems that you see in other post usually happen when the New Relationship Energy slows down and people start to notice differences and challenges more.We fell into a triad fmf 6 months ago. And it just keeps getting better. All the problems we have seen in other posts just don't happen, no jealousy, just the opposite in fact, no difficulties, great communication, blissful sex, loving and cherishing any time we have, respectful extacy. Not sure why, perhaps it's because of just two things,
1. All three of us are madly in love with each other and proud of ourselfs for that. And not the slightest bit jealous or selfish.
2. We've had lots of life experience ( we are old 45-60) so know how to handle the mundane stuff like, time, money, coming out, children etc.
Advice, grow up first, and if you are amazingly lucky, unplanned, fall in love.