You are very well informed and open minded. That's really great! That's the first step to getting marital bliss.
Many men with ED and other sexual problems find it awkward to seek help for their sexual issues. This is a pity as many of the concerns can be properly addressed and treated. Oftentimes, their partners also suffer and many of them suffer in silence.
You can talk with a psychiatrist who is experienced in helping couples with their relationship and sexual problems. For young people with ED, very often the ED is due to anxiety, work stress or psychological problems. ED due to stress occurs suddenly and oftentimes there is a clear precipitating cause. Another way to determine whether his ED is due to medical problems or psychological factors is to find out whether he has normal erections in the morning and when he masturbates. For psychological ED, usually the morning hardness and erections during masturbation are not affected.
The psychiatrist can talk with you first and then later on arrange to see the two of you together. If it is conveyed to your husband that he needs to come for a session so that the psychiatrist can help you, he is likely to show up for the subsequent session. If you tell him that the problem lies with him, he may feel offended and will not come. The way to tell him is that the psychiatrist needs to enlist his help so that the marriage can be better. A marriage involves two persons, so oftentimes the psychiatrist need to see the couple together.
Do not give up. It is important to seek treatment early so that there is marital bliss! Cheers!