i think locking him out is the worst thing you can do. Why don’t you speak to him and show him respect by giving him a key, explain that like you are respecting his wishes and giving him a key, He also has to be considerate to u, tell him that you worry about him and it gets you nervous when he comes home so late, maybe discuss a time that he should b home latest…
Also, and this is soooo important, someone who was OTD told me this helped him come back “on” show him loads and loads of love!
Good luck!!