is he ready

my boyfriend cheated about 5 months ago and ive had a hard time getting over it he is 32 im 39 we live togtheer he doesnt have a regular job but he does work he doesnt help with the bills and he would rather buy weed than get a regular job his friends r always calling for him to go smole or drink and i talked to him about this several times told him i didnt think he was ready a serious realationship because he dont have his shit together when ever we r supposed to do something he either is very late or just forgets about it and go with friends now i talked to him and told him i was tired of it so at christmas he gave me a engagment ring but he wont tell anybody were getting married i have to tell people and when they ask him about it its like he dont want to talk about it just changes the subject im very scared to even marry him because im afraid he will cheat again with his ex or i will end up living with nothing like his family because he dont want to stop smoking and get a job ive tried to help him in everyway but u cant help someone if they dont want to change i really dont know what else too do ??

NO, he isn't ready.

Sounds like he gave you the ring and to shut up your mouth and so he can continue to do what he does.

He's trying to keep you sweet.

If this ring meant anything, he'd want to break the news you are getting married, rather than keep it hush hush.

Why are you with this prick?

To be honest, he sounds like a complete loser and he doesn't want to improve himself. You can't help him, if he doesn't want to help himself.
You are right to be scared of marrying him. I would expect it to get only worse. I doubt that he gave you a ring for the right reasons, as he doesn't seem to put any effort in your relationship.
I am sure you can find yourself someone better - more responsible and trustworthy.