My boyfriend keeps tearing my vagina

Lily

My vagina is pretty tight and always has been! Sex used to be quite painful sometimes and it’s always felt like I’m being stretched. But with my new bf it was fab at first but now I keep getting a small tear at the bottom of my opening, making sex sore. My boyfriend is big but not insanely huge. I’m not sure what to do about it or how to fix it?! Please help!!