If you've been reading, then what I say won't be new.
You're only 3 months out. You have an incredibly long way to go. Right now, while not ignoring your pain, you need to focus on your Husband's pain. Hopefully the time will come when he can see why you're hurting and support you.
On SI, read all the threads, not just Wayward Side. You can get great information that will help you understand where your Husband might be and you can "meet" others who have been where you are.
Also, there are so many resources out there. My Husband and I have a stack of books which we used to help guide us back toward each other. There are also other websites (although I haven't found another one quite as user-friendly as this one).
Life after an Affair is a hellish roller coaster of emotions and hard truths. Demonstrate your desire to be a better wife to him by your actions! Every single day, get out of bed thinking about him and what you can do for him that day. Be specific. Listen carefully to what he has already asked of you; don't make him ask again.
I think your question about moving past without understanding might best be answered by the BSs out there. What it means to understand is probably a bit different from person to person, IMO.
It's not easy and sometimes it really sucks, but this is the reality we each created.