He's soooo hott/gorgeous/cute/funny/smart… but his p*nis is TOO small.?

it seems like 3 or 4 inches. he says it's 5. and i just cant climax from him, i always have to fake it. im in love with him and we've been dating for 9 months. he cant stay hard sometimes and we dont even like the way the other kisses. what do i do? stay with him and have an unfulfilled sex life forever? we're both 24. he loves me now but he's no longer IN love with me, should i cut him lose? i love him too much to break up with him and i would be too jealous if we were just friends and nothing more.