My bestie has changed so much

I don’t think I can trust my best friend anymore, and this causes me a lot of pain. At the same time, I don’t want to end our friendship because I feel as if that will be a mistake. People change, and I know I can’t expect him to stay the same, but it sometimes feels as if he doesn’t have my interests at heart. He says things about me behind my back. We still meet often and there is a lot of laughter, but it now feels artificial. Maybe he’s still friends with me for the same reason, because we have known each other since childhood. Should I end it knowing it’s causing me harm, or wait in the hope that he realizes what he’s doing? I don’t want to regret losing a friend.
Why don’t you consider telling him how you feel instead of weighing the pros and cons of not having him in your life? Any real friendship is based on the ability of people to be themselves and be honest about how they feel. If this person is causing you harm, and you don’t call him out on it, you won’t know if this friendship is as valuable to him as it has been for you. People do change, and drifting apart from an old friend is normal, but it shouldn’t be done without communication. If nothing changes after this conversation, you can make a decision knowing that you gave him a chance. At that point, the onus of making things right will be on him.

A few years ago, I ended a relationship with someone who was a soulmate, and I think about him every day. I am in a good place but sometimes wonder if I did the right thing. Should I reach out to him?
You won’t know how he feels without meeting him and talking about it. At the same time, you should be aware of the possibility that he may not reciprocate and has chosen to move on instead.