Oy, this is a biggie!! the loss of your childhood with the attendant need for play, security, safety, love, guidance, physical affection, and time to be completely taken care of and nurtured is a massive trauma. I was a preternaturally 'mature' child by the age of 6 or 7 - doing housework, chores, getting up and getting myself ready for school completely on my own and racing to catch the bus on time - who didn't know how to play, giggle, be un-self conscious. I was serious all the time, and it took a terrible toll on my ability to make friends and feel connected to others as a child.
First you absolutely need to understand how severely parentified you were, and how this pernicious belief that you must take care of everyone else but yourself is going to do you in if you don't manage to break that pattern. Do the research, if you can get therapy go for it, and start every single day, reminding yourself that you must find ways to love and take care of yourself. Do your best to get rid of all the leeches in your life, or at the very least learn to establish boundaries and SAY NO. People pleasing is rife in those who have been forced to grow up prematurely. There's an excellent book by Harriet Breaker called The Disease to Please: How to break the People Pleasing Syndrome that was a real eye-opener for me. It made me furious to realise how I'd been duped by my upbringing into being such a doormat for others and neglecting myself on so many levels!
You must learn to stop serving others and root out that submissive mentality that leads you to believe that you're not important and that your needs mean nothing and that you're bad for asking for what you need/want. Otherwise you'll always be vulnerable to exploiters and abusers who sense your lack of inner self and your need for external validation and acknowledgement. It's SO worth getting a grip on this issue - the feeling of empowerment when you do is tremendous.