I went through something similar as well! I had to drop a lot of friends in order to keep looking forward to my sobriety! I still manage to keep onto 2 of them but that's only because they supported me! Yes, I was heartbroken at first!
I've been working the steps and recently just finished step 5! Mean while I have thought about the friends I've lost but realize if they were truly friends they would support me and want me to get better than out drinking! Sometimes it hurts when they don't support you but in the long run you will be a happier person if you continue to work on your sobriety!
On a good note! Since I've been going to treatment and AA regularly I have found and made so many new friends from all races, ages and genders that I'm happy to call them my friends and I know they are supporting me and want to see me moving forward!
Stay strong and keep moving forward into your sobriety! It does get better if you believe and use the tools that are put in front of you!
Take care,
DBJ