Hi, OP.
I just wanted to offer a mumsnet hug to you. It sounds like you have had so much change in a short space of time. A year really is not that long.
Wanting some intimacy from you husband, who is not giving any out, is going to be upsetting. You have tried a lot of things from the sound of it, he's now just ignoring it.
Can I ask have you tried to move away from penetration, seen as this is the root of the problem for him from the sound of it. Maybe talk about other ways you two can still share intimacy. Him sleeping downstairs is not going to do any good, although I understand about the snoring.
Going right back to the basics, cuddling? Kissing? Feeling? Stroking eachother? Does he seem interested at all? Does he know what you like? Does he know how to use his hands? You two can even use toys. Sex is not so black and white, you know this but does he?
Does he think "oh because I can't keep my dick hard that's it, game over?"
You two really need to talk and try to move past this, if he is not going to try and get any help now for his erectile dysfunction, you need to talk about other ways. Keeping the intimacy alive is so important, for both of you.
However if he really is just not into you at all, don't waste time with him. You two can stay friends but divorce. Your sex life is not dead just because you are in your 40s, bin him off if there is nothing there. He loves you but is he in love with you? Does he want to make you happy or just make you tea an toast in the morning?