Struggling with Loneliness and Lost Friendships After Divorce

My wife left me 9 months ago. Romantically I've moved on and have a new girlfriend, but I lost a lot of friends and people that I used to interact with. Lately I've been feeling really lonely and have been doubting some of my remaining friendships. One of my oldest and closest friends has been distant since the breakup and it seems like she's taking my wife's side or values her more than me. I've really tried to keep the divorce friendly, but sometimes my ex makes that very difficult. I fear that I'll lose more friends before this is over, and that I'm bad at making new ones. I've also recently been trying different meds, which have helped me with anger and anxiety, but i still feel like she demonizes me for my past difficulties whenever we fight.