There’s not much I can add here, Rikki, as whatever I’d say, has already been posted.
I’ve been down this path before, and yes it hurts, and yes, you wonder if you could have done this, or if only I’d do that, but the fact is, sometimes, these things happen despite your (or your parents) best efforts.
Never give up, and never say its too late! This past week’s Ami had a story of a WW 2 survior who left Yiddishkeit and came back after almost 65 years! Why? No one kmows what it was that sparked the return. But thru a good portion of his being away, he was in contact with a childhood friend, who did not do a full court press, but at the same time, never gave up hope for a full return.
I’d guess that your brother is under 25 (perhaps even under 20) so there’s every chance that what he is going thru is just a result of being a young person in a very confusing time of life. You might consider having him join the CR, as the issues that are bothering him might be something we’ve been thru and can help him work out.
Don’t give up, Rikki. Not on him, and not on yourself!