An alcohol or drug relapse does not begin when you pick up your drug of choice, it is a process that begins long before actual use.
I wish I had seen these signs in my own relationship with my partner. Recovering from drug and alcohol dependency is a hard road, and it requires the love and support of family and friends, and those romantically involved in your life. Be there for them, pay attention to changes. Also, know when to detach so that you don’t get taken down in the process.