I feel horrible like i want to die. ?

I just told him I couldnt marry they 45 year old man I love. He left me. I am mature enough to have a marriage with him. I love him. And yes when he asked me to marry him i said yes. But i was overwelmed. I wanted to marry him. My whole family hated the idea. I tried to tell him to take it slow. But he got really angry and left. He just texted me and told me that He was sorry that he stormed out. But i just want to die. I really wanted to marry him and because everyone in my family, and close friends said it was a bad idea and i still wanna date him. How do i get him to come back and talk. What do i do. I am 21 Btw.