It's somewhat telling when you say, "I seem to be putting in more effort than they are."

If they consider you a friend then it should be super easy to hangout with them, perhaps they don't consider you a friend anymore or there's some other change. Friendship is a two way street. I will never hangout with a person who doesn't want to hangout with me, I value my time and no matter how much I like them, if they don't like hanging with me I'll never hang with them.

I have a Friend who complains that no one hangs out with him and that's he's making so much effort, the guy is a nice guy but he's exhausting to be around. I consider him an acquaintance but I know he wants me to be his close friend. He doesn't get it, he's exhausting to be around emotionally and mentally. He's always making efforts to do things but he doesn't make me feel comfortable. Yes the best thing is to communicate to him how I feel, but I avoid confrontations, yes it's a vice of mine and I'm working on it. But I have my close friends and I don't care to add more, I hang with him sometimes but I'll avoid it if I can. He's genuinely a good person but he belittles people's opinions and I know if I tell him how I feel it'll likely become an argument. I don't have enough energy in the world to make everyone my friend. So I choose to just nod along with a fake smile most of the time if I'm with him. I hang with his brother more often, and he always wonders why I'm hanging with his brother more than him.