How to leave?

How do you become strong enough to leave a 3 year relationship? Both 20 years old and you ‘should’ve left’ ages ago but you chose to stay with the person you love when he doesn’t feel the same way back. It’s been really hard the past few months with multiple breakdowns from both sides. He’s had enough but I still love him and don’t give up that easy. I know relationships take effort from both halves but I don’t know what to do. He doesn’t feel the same way as I do..... some advice please. I don’t have any close friends and I also don’t have a good relationship with any family. It was just me and him, but if I become strong enough and leave... I’ll be alone. It’s my first break up and I really thought we would get married. We talked about moving out and starting our future. I’m lost.

Asking for a mate (the mate is me) xx