Cass ~ I'm so sorry you're feeling unappreciated.
One thing I've learned in my 40+ years. You can't please everyone. You have to please yourself. Trying to please others is a waste of your valuable time. You could be the most perfect (whatever that is) human being that ever walked the planet and someone would have something nasty to say about it.

Don't clean the house because you want your room mate to appreciate or validate you. Clean it because you prefer it that way.

And, at the risk of sounding like Dr. Phil ~ you teach people how to treat you. If you are feeling ignored, unappreciated or taken advantage of by several people in your life, it could be that they have taken your helpfulness and goodnatureness as a sign that you are a "doormat".

Now, they aren't going to like it when their little kitten shows her claws, but that may be what you have to do. Demand respect!

You sound a lot like me when I was in my 20's. Like was a lot happier once I stood up for myself. Good luck!