I've been diabetic for 17 years now and for the last 8 or so years I've been having issues getting and sustaining an erection. I've tried different natural medicines to try and help - Muira Puama, turned on Goat Weed and Siberian Ginseng tinctures; ginseng root; zinc and l-arganine capsules and lately I've started taking Ashwagandha root powder and KSM-66 tablets as they're supposed to be very beneficial for my situation. I know that these can take a LONG time to have an effect but is there anything I can do to treat this condition - even if only for one night at a time (it's getting a bit tiring telling partners that I can't get an erection and watching the relationship crumble from then on)?

I mentioned I'm diabetic because over the years doctors have told me that it might have an effect on erections but they've never done anything about it. thats what made me try natural medicines in the first place. 

By the way: I gave up smoking about 5 years ago and I've never been one to smoke marijuana. Also, I only have a couple drinks at the weekend, so none of these should be the cause of it, right?