Stuck- should I stay or go?

Tara
So my boyfriend and I have been together for about 4 years now. We have a beautiful 21 month old son together! For the most part, he's a wonderful and loving father. He is crazy about our little man just like I am so there is no issue there. The main issue is that he isnt a strong partner or one that helps with the ongoing responsibilities as a parent and a spouce. When we met, we clicked instantly. He had such a natural charm about him and I loved how I could have an intelligent conversation with him. Over the course of a few years he became exceptionally lazy. He was probably like that all along and I failed to notice or he hid it extremely well. I am in school, have a full time job and with no immediate family around, I have our son the majority of the time because we work opposite shifts and since he's on night shift, I have our son every morning until I go to work on second shift. So to the point, his laziness is becoming increasingly intolerant. I will ask him to help me with something small like dishes or whatever and he (with a few expectations) just won't. I am having a really hard time managing the entire house, caring for our son, working, school and schoolwork. I know I chose to take on a lot but I have been in school and worked full time since we met so that's not new. I have told him I really need some help or could use an extra hand and he just doesn't get the point. He also leaves his trash all over instead of throwing it out, leaves clothes all over throughout the house, leaves used q-tips out and all that. I've tried to lower my standards, I've been sympathetic to him and I've asked what I can do for him and all that. It hurts my feelings and he ever has a valid reason why. He will just play on his phone and Xbox while I do everything. I'm getting exhausted and I feel like it's not my place to force him to change because at this point, he probably won't. We've been through this over and over for at least two years and although there may me a slight brief change, it always ends up back at square one. I'm tired and feel disrespected, unappreciated and hurt. What should I do??