I need some help

So my husband and I used to have sex very frequently and now not so much. He and I were talking about it because I was upset and tired of getting rejected all the time. He has depression and I know that and we have been trying to work on it and he's seen a doctor but I've never gotten him to agree to see a therapist or an actual psychiatrist. He finally agreed tonight, but he also told me something that really scared me. He told me that he has thought about suicide and he even has a plan but would not do it. I'm having an internal delema on what I should do with this information, besides make him an appointment asap with a doctor. I'm thinking about telling his brother, his oldest the one he looks up to in hopes that he could have a guys night or whatever and make it more of a priority to hang out with him instead of constantly blowing him off. But I do not want my husband to not trust me to tell me things.