How Can I Get My Husband To Express His Feelings Without Overwhelming Him?

Speaking as a man if I had to deal with a person that trough me away like yesterdays news I would be difficult to be around to.as far as him pushing his adoptive parrents aside, you did not mention if he new his whole life that he was adopted. If he did and he sa to find his birth mother than he should have prepared himself for what emotional bagage that was bound to come.than again how could anyone prepare fore the unknown?
Now if he just found out late in life he was adopted that had to rock his world to find out that the people that raised and loved him for so many years wear not his biological parents. That would definitely cause some one to close off.
   My advise is to give him all the love and support you can. And you may consider giving him some space but not to much.be as understanding as possible and remember men tend to deal with difficult issues like this closed up. When he is ready to talk about it he will just be prepared because once he dose start you probably will not be able to get him to stop.it may end up being like one of those sessions woman have when there life goes wrong and he may do all the talking let him and just show him love and support.