When I was 2 years old, my father passed away. About 10 years ago, my mom said something to me that I'll never forget.
The part about grieving no one thinks about is what happens *after* you stop paying attention to the person grieving. What happens 2 months in? 6 months in? I remember my mom telling me how lonely she felt after the dust had settled and people thought they didn't have to check-in on her anymore.
One thing I've noticed as I'm currently going to therapy for my "delayed grief reaction" (thanks, Marty, for the term!) is I'm separating from my old friends more and more. Frankly, I don't want to talk to them. I make excuses like I'm busy, don't call them, I'm slow to respond to their texts, etc.
The only thing that fulfills me somewhat is meeting new people who deeply understand my grief and pain -- people in my improv class and ManKind Project groups.
If you haven't already, I'd look into therapy, group counseling, church...SOMETHNG where you connect with people at a more deep, authentic level.
Best of luck,
-David