I can't not worry!

I've read some stories about girls being insecure and worried that there boyfriends will break up with them, and trying to control them because of this. I get worried for a different reason - whenever my boyfriend goes out, especially at night, I get worried that something will happen to him. I don't want him to think that I try to control him but I always try to convince him not to go out with his friends incase something happens to him, not because I don't want him to have friends, but because I think that its dangerous to go out late at night and do things, no matter how old you are. My boyfriend is 20 and sometimes feels that me asking him not to go out because its dangerous is me treating him like a child, but its not because I don't go out at night to any clubs or bars either because its dangerous. A year into our relationshiu he was severly injured at night-time and nearly died, he was in hospital for weeks and couldnt walk properly for months. I found the emotional and physical implications of this injury hard to deal with at the time because I had to look after him, and it would upset me to see him in pain. I was attacked a year and a half ago(were we together at this point) at night time and I think that these things might have made me overly cautious and anxious. I recognise that I sometimes act irrationally but I can't help it, I always think that it is better to act this way than to risk anything happening. I am also scared when he leaves me in the house by myself at night to go out, and I am worried that something might happen to him while he is out or to me while he is not with me. Because of this I get very upset and even angry when he goes out at night with his friends, especially when he drinks because I feel that this increases the chances of something dangerous happening. I'm not agoraphobic I'm fine going out usually, just not late at night in areas which I find scary. He isn't as cautious as me at all and likes going out late to parties/clubs/bars and drinking. I do not like this and I sometimes try to prevent him from doing this. I don't want to push him away by being to controlling but I can't help being worried. What should I do?