@Magda72
People entering into second or subsequent relationships generally bring more baggage and more people who will be impacted by these relationships and yet they seem , if what we read on this site is accurate, to do far less exploration and discussion of even the most basic issues. We see people not having in-depth discussions about parenting, partner expectations, finances, pre-existing/current debt, long-term commitment to assisting adult children, expectations regarding assets that partners bring into the relationship, prior commitments to the type of education to be made available for existing children, firm commitments and desire to have additional children, etc.
Seemingly ,many of these people only become aware of these issues as subjects for in-depth discussion after they marry or move in together.
Who buys a house with someone to whom they are not married without deciding prior to purchase how the property will be split or disposed of should the relationship not work out as expected? When you marry or move in with someone having had one or more failed relationships between the 2 of you, you are not some naive child wearing rose colored glasses.
You are an adult with enough life experience to at a minimum know what issues can and should be discussed and sorted prior to moving in, making joint property purchases , or marrying. Failing to discuss and ascertain if you are truly on the same page is choosing to be willfully ignorant and grossly negligent.
Sadly, it is one thing to conduct your own life in this manner, but to bring your children in to such a poorly informed situation is close to unforgivable.