I am 10 months in and still have these feelings. It gets better with time. Its hard, but it gets better.
In the beginning,for me, knowing what they did was just just too painful. The main thing i did to help me thru it was to talk to my WH and find out what they DIDNT do together. I needed to know what was still mine, what he never gave her, what they never shared. I know they never had shower sex...they never took a bath together or had bathtub love...they never gave each other massages...he never surprised her/set up a romantic encounter for her with candles/soft music/incense like he did for us...he never gave her gifts or flowers or things of that nature.
Finding out those things has helped me to deconstruct their A....see it for what it really was.....being able to deconstruct it has helped me tremendously.
If knowing what they did is too hard for you....try this approach....get stronger...process. Then, when you are feeling more secure, start asking the questions about things they did do.
hugs to you