70% of second marriages after divorce end up splitting because of the children of the first marriages. A parent who has remarried will always place their child before the new spouse.
The new spouse in a "blended family" has little to no authority over the children. When the child goes back to their other bio-parent for the weekend, they handle the children differently, usually more leniently, causing anger toward the other bio-parent when they return for the visit with the non-bio parent.
It is normal and natural for bio-children and parents to cater to their own bio family.
Do you now see why God said not to divorce and not to remarry? When God made two people one in marriage, gluing them together with a spiritual glue, He knew the disaster it would be when parents divorce and what would happen to their children.
Bio-children have a bond with their parents that no one else can have. Even with adopted children, we see they do not fully bond to the adoptive parents, in most cases going off later in life to find their biological parents. Because of this I see the bond is more than physical traits, it is a spiritual matter that most people do not recognize.
Moses went back to his bio-family after being raised from an infant in the Pharaoh's house. He was connected to the royal family until he discovered they were not his bio-family. After that he sought to go back to his bio-family.
Children who have to be shuffled back and forth between bio-parents become angry. They don't have two homes; they have no permanent home, and they feel it.
1 Corinthians 7:10-11 "10 But to the married I give instructions, not I, but the Lord, that the wife is not to leave her husband 11 (but if she does leave, she must remain unmarried, or else be reconciled to her husband), and that the husband is not to divorce his wife."
God has good reasons for telling us His commands; they protect us from ourselves when we are at our lowest. When we no longer have the strength to figure things out because of emotional pain, we can look to His commands until we come to our senses.
Doing anything from emotional pain is a huge mistake, it does not allow us to see that even though things may be hard in the moment, there are lessons learned and situations change when all is better again.
Most divorce and remarriage situations are because people are ruminating on their feelings, becoming bitter, and refusing to see the side of the other person.
Rather than going to prayer, asking for determination to obey God inspite of the emotional pain, those who are willful defy God's Word and follow the easy way of the world supporting them in their sin, even making them feel justified for doing it.
1 Corinthians 2:14 "But a natural person does not accept the things of the Spirit of God, for they are foolishness to him; and he cannot understand them, because they are spiritually discerned.'"
When we follow the world, we can be temporarily comforted, but emotionally and spiritually, we regress in all that is important!
The more we regress, the less we are able to see the wisdom of powering through what is important.
James 1:2-15 "2 Count it all joy, my brothers,[b] when you meet trials of various kinds, 3 for you know that the testing of your faith produces steadfastness. 4 And let steadfastness have its full effect, that you may be perfect and complete, lacking in nothing.
5 If any of you lacks wisdom, let him ask God, who gives generously to all without reproach, and it will be given him. 6 But let him ask in faith, with no doubting, for the one who doubts is like a wave of the sea that is driven and tossed by the wind. 7 For that person must not suppose that he will receive anything from the Lord; 8 he is a double-minded man, unstable in all his ways.
9 Let the lowly brother boast in his exaltation, 10 and the rich in his humiliation, because like a flower of the grass[c] he will pass away. 11 For the sun rises with its scorching heat and withers the grass; its flower falls, and its beauty perishes. So also will the rich man fade away in the midst of his pursuits.
12 Blessed is the man who remains steadfast under trial, for when he has stood the test he will receive the crown of life, which God has promised to those who love him. 13 Let no one say when he is tempted, “I am being tempted by God,” for God cannot be tempted with evil, and he himself tempts no one. 14 But each person is tempted when he is lured and enticed by his own desire. 15 Then desire when it has conceived gives birth to sin, and sin when it is fully grown brings forth death."
We miss the lessons from persevering and eventually become infant-like in our responses to life, making more mistakes than we would have if we had just obeyed God. And worse, becoming less wise, when in our elder years we should be prudent and sensible.