This is something I know far, far too well. I was on Lexapro for 15 years. I started drinking about 5 years after starting Lexapro. SSRI's are powerful drugs, they can and WILL change your brain chemistry. For some people they are lifesavers, for others they are as bad or worse than alcohol.
Coming off them can be *INCREDIBLY* difficult, people (like me) have debilitating panic attacks and other symptoms that are often worse than the ones we went on them for. Some people feel they can also lower your inhibitions, which can be a dangerous thing for people living with addiction.
That said, if you feel you need them, then as others have mentioned, these drugs can literally save lives for people who have real mental illness problems. I would just personally advise someone to really make sure they need them before they start, and stay in close contact with your DR. Good luck.