The father has consistently compared the original family to his girlfriend's, disregarding their history. Expecting the daughter to babysit his girlfriend's child while he goes on a cruise is insensitive and disregards the emotional turmoil it causes. The daughter has every right to prioritize her emotional well-being and maintain boundaries, especially given the family's complex history. It's about self-respect, not selfishness.
The daughter is clearly struggling with unresolved resentment towards her father and is using this babysitting request as an excuse to create drama. While the father's behavior might be insensitive, the daughter's refusal seems rooted in a desire to punish him rather than a genuine concern for her emotional well-being. She should stop acting like a victim and address her issues directly instead of dragging everyone else into her mess.
The father's request is undoubtedly insensitive, considering the family's history and the emotional baggage involved. He should be more considerate of his daughter's feelings and avoid putting her in such a difficult position. However, the daughter also needs to communicate her boundaries clearly and avoid passive-aggressive behavior. Both parties need to engage in open and honest communication to resolve their issues.