Husband can’t perform

Advice please.

My husband is 46 and I’m 33. We have 5 kids.

We never gave sex anymore because it always ends in disappointment because he just can’t stay up.

He’s a smoker, drinker and smokes weed so none of that helps.

But he straight up refuses to get medicine to “help” him out.

The last time we had decent sex was in July. Here we are mid October and have attempted sex less than 5 times.

I just don’t know what to do anymore. Sex is very important to me but I sure feel like shit when he’s up maybe 5 minutes and that’s it.

It’s crushing. Disappointing. Hurtful (only because I feel like maybe he’s just not attracted to me anymore).

Any advice??

EDIT TO ADD

YES HES COMPLETELY SOBER AROUND OUR CHILDREN.

He doesn’t drink until the kids are in bed and hes never stupid/incoherent drunk. And weed is legal where we live