You're not alone in experiencing this if that is any consolation. It's kinda a "nice guy" syndrome thing. You give your time and attention and energies to show people you care about them and you want them to be happy and then it doesn't come back to you. You would think people would naturally reciprocate but unfortunately that's not how it works most of the time.

What I have found is that people can be confused if they aren't certain who you are and what you stand for, what you want for yourself. If you give to others but never make it clear what you want for yourself in return then they'll just take and assume you're happy with the way things are. In a relationship it's ok to express what you need too. You said you struggle with low self-esteem so sometimes being more assertive can be difficult. I am not saying you have to be pushy or insistent, simply communicate is all. If you wonder why you always have to put things together then ask your friends if they don't mind doing it sometime. If they are real friends they aren't going to mind carrying some of that burden. Maybe they have just figured that's your thing and you like to do all the planning so they are letting you do that. If that's the case then you need to correct them by letting them know.

Take some time and define yourself for yourself. Decide what YOU want out of relationships. Realize that you are just as deserving as anyone else to be happy and the people who are your friends play a role in that. Communicate and make it clear to them how you feel and what you need. Again, if they are good friends, they aren't going to mind and they might even be pleasantly surprised. I have had to make changes like these myself and it has really helped.