Could this be my problem?

I have been trying to get pregnant for a year and a half now with no luck, not even a scare. The women in my family have never had a hard time getting pregnant, you can look at my sister and it happens. Lol. I like to drink, and I do so probably 3-4 times a week. Does anyone think this could be my problem? I've looked it up and got wishey washy answers. Any advice?