Why is drinking alcohol a problem on effexor (venlafaxine)?

Several problems: Effexor (venlafaxine) may be used to treat depression or anxiety. Alcohol may make depression worse and may hinder one's ability to cope w/ anxiety. Also, i worry about people who are afraid to "give up alcohol" or can't see themselves never taking a drink again. Why would you want to potentially sabotage your treatment for a drink?