So Indy below is my mantra on how I live my life. I read this at least one a day.
“A true alpha’s state of mind is one of indifference, charm, humor, humility, courage and a belief that eventually, things will work out in their favor. Alphas set, keep and hold other people accountable to their boundaries. They stand up for what they believe in and don’t compromise their principles or values for anyone. They have an emotionally compelling vision of what kind of life and lifestyle they want to create and then resolve to pay the price, no matter how long it takes to make it a reality.”
So in relationships moving forward for me infidelity is a boundary. You cheat you're out. No exceptions. In friendships if you are not loyal and do not have my back you are out. No exceptions. I will never ever again try to convince someone to be in my life who doesn't want to be there.
I think you need to figure out what are your principles and values. If it's monogamy then that needs to be a boundary and cannot be compromised for anyone and you need to stand up for what you believe in.
M(53), W(54),D(19) M-23, T-25 Bomb Drop - Dec.23, 2017 Ring and Piecing since March 2018