About parenting - what we need to do is take responsibility for our actions. If one parent absents themself, effectively, from a child's life, we are not the one doing the excluding.
Again, if the children are adult, I think it is OK to discuss the strong probability of MLC with them.
If one parent voluntarily excludes themself from their child's life, all the other parent can do is keep the door open for a change of heart, and not plant false ideas (either pessimistic or optimistic) in a child's head.
just my 2 c. Don't beat up on yourself. Children can easily feel it is their fault if one parent is not in their life.
