Sound like you're capable of reflecting and growing, which is awesome. You don't need to be hard on yourself or your friend. You might just be becoming mindful that you need other friendships that have other qualities to them, than the friendships you've had in the past had. This is just growth. Also making new friends is super fun. It's a bit challenging to "put yourself out there" and all that, but all of the best things in life are hard. I really like cheering for my friends, and lots of other people do too. You can find these people now that you know what you're looking for.

Also I've never had much luck with work friends. Work seems to get in the way. These days board games are my best strategy for maintaining friendships. You need some sort of "third place" for maintaining good friendships: https://en.wikipedia.org/wiki/Third_place