Purdah

Purda from foster relations

Q: I have been adopted by my Paternal Uncle (fathers brother) due to him not having any children. My Uncles wife did breastfeed me, making her my Foster Mum. My Question is regarding parda with the following people, and making Salaam and shaking hands with them. Are the following Males, Mahram to me:

  1. My Foster Nana (foster mums father)?
  2. My Foster Nana's Brothers?

And is Parda required between my Husband and the following females:

  1. My Foster Mum?
  2. My Foster Nani (foster mums mother)?

*** Both of my Biological Parents are still alive ***

From what I understand, that all relations that are Haraam through Blood are all Haraam through Breastfeeding also. Please shed light on the above Laws, and if any other rules are to be known, please inform me.