Dreams involving animals, especially vulnerable ones like a kitten, often reflect our feelings of responsibility, care, and the need for nurturing. In your dream, the grey kitten with an eye infection and parasites may symbolize a part of your past or a relationship that needs healing. The fact that it was living on the streets and eating vomit suggests feelings of neglect or being in a difficult situation.

Your refusal to take care of the kitten could indicate a reluctance to engage with unresolved feelings regarding your ex-girlfriend or the relationship itself. It may represent an unwillingness to face past issues or responsibilities that you feel are not yours to bear.

The name "Rodney" could also carry significance; consider if it has any personal meaning to you or if it symbolizes someone or something in your life.

Overall, the dream might be prompting you to reflect on your feelings about past relationships and responsibilities. It could be worth considering whether there are unresolved emotions or situations in your life that you need to address.