A boundary is when you won't accept certain behavior without consequences. If your kid breaks curfew then the consequence is he is grounded.
With your spouse (another adult) we don't have the authority to enforce our will on them. So out of respect and love we need to adhere to the boundaries we have in our relationship.
The consequences might range from telling your spouse they are out of line to I am filing for divorce. Boundaries are based on behavior that is unacceptable to you. Your feelings/gut are a starting point to what they are. Then you need to think thru the feelings to understand the why it is a boundary. Some things that upset me might not upset you.
Lot's of info on-line about boundaries.


M22,H45,W45 S21/18D12
Retain faith that you will prevail in the end, regardless of the difficulties and at the same time confront the most brutal facts of your current reality, whatever they might be.