Rumination

My therapist gave me a hypothetical question: "How much money do you want to feel content?". It didn't take long for me to respond with "Maybe like $3-4 million?". My reasoning was that I thought this was enough to "protect" my family from unexpected health conditions / incidents (at least financially) and then some for myself. This q&a by itself didn't mean much, but I think on this on top of the other topics we discussed that lead to this question, my therapist asked me to look up rumination. I think he suggested that I do a mild form of this and to practice being aware of it.