Hi,
You might start by going into a little more detail about your situation, like what drug he used, for how long, how long you have been married, if you have kids, and what it is that you are feeling about all of it, stuff like that.
Oh, and welcome to SR! There is a lot of good info here, check out the 'sticky' posts at the top, and feel free to post as much as you want to and ask anything you want to ask. There are great people here who will be happy to give you all the support you want.