That's an extremely hard question to answer.
Notice that if you are primarily self-concerned ... well, it's very unlikely that anyone but yourself is going to have much interest in your life. If all you care about is entertaining yourself, or complaining about your problems, or even getting better, there's not much for people to bond over. (Though it also explains why people like people who appear to take an interest in them.) You need to be interested in something bigger than yourself.
This ties in with stuff I've said before: people won't spend time with you if you're not making their life better somehow.
Yes. People like people who take an interest in them. I feel that that is the basis of my relationship with my wife. She says that she was attracted to me because I have a "different way of thinking", whatever that might mean, and that I "make her laugh". This came across to me as her being very accepting of me, which made me feel valued and liked. Also, she was rather needy in some respects, but still able to stand on her own two feet and effectively deal with any challenge that came her way, but I felt I could fulfill some of her needs.
Nothing thrills me more than being able to please someone, and I couldn't stay away from her, and just wanted to be with her. l have found that this has been a excellent reason to be married, although neither her, nor my, sexual appetite is properly satisfied. I'm gay, and she doesn't experience any sexual desire on my part, but a great desire to please allows me to sexually satisfy her.
So it works and I am not complaining. She understands our situation and does make certain allowances for me. But neither she nor I entertain the idea of an open relationship. A person has to be young, energetic, and a little bit crazy to try that. I've got it very good and nobody has a perfect life, so I am not complaining so much as looking for ways to make life even better, by becoming a kinder, more trusting person.