Welcome to SR. I am glad you found us, but sorry you had to.
I would certainly get to a Dr and get checked for any and all communicable diseases. One cannot walk into a drug store and say they are a diabetic and get syringes. One has to have a prescription from a Dr. So please get yourself checked out.
Based on what you have posted does not sound like your H is an ex addict but is still in the throes of his addiction.
What you can do for YOU is find some Naranon or AlAnon meetings. You will probably find more AlAnon at more convenient times for your schedule. Unfortunately there is nothing you can do to help him. He has to want recovery for himself. The 3 C's can work very well for you:
You didn't Cause this.
You can't Control this.
You can't Cure this.
AlAnon will help you with setting boundaries, how to detach, how to work on you, etc and give you some face to face support also.
There is a great book called "Co Dependent No More" by Melodie Beattie that has done wonders for many of us. It is available very reasonably at Amazon. Please read it with highlighter in hand. Then when you are done with it for the first time, go back and write about each thing you highlighted. The next you read it, use a different colored highlighter, lol
Check out the 'stickys' at the top of this forum and read some of the different threads. Ask questions any time, there are many on here who have been where you are or are where you are and will share what worked for them.
Please keep posting and let us know how you are doing as we do care very much.
Love and hugs,