Please don't turn your 6 months into 6 years. If I were you, I would leave now before marriage and baby comes and then it will become much harder by 100 fold. If you are already feeling lied to, angry, resentment etc. you will feel it much more with every month or year that goes by without any change from him. The advice from the ppl, above are right. The change will have to happen from him, when he feels like he has to make a change to want to be sober. Unfortunately there is no telling when this might be. It can be soon (which probably is unlikely), it can be in years or it can be never. You need to ask yourself whether it is worth it for you to be sticking by with an alcoholic because it will mean that you have to stay strong, stronger than he is to hold together the broken pieces caused by an alcoholic. You need to (even though it's tough) be able to have open communication with him. The more you nag about the alcohol, the more he will lie to you about it. After all, he is trying to protect the thing he feels he NEEDS (alcohol) and an addicts mind will do things (as low as it may be) to protect their addiction. It's much healthier for the relationship to have a trusting, open communication. Knowing he will lie, you need to change your tactics of communicating with him. If you don't be prepared for a long, exhausting and stressful journey of paranoia. He is addicted to alcohol, you'll quickly be addicted to making sure he doesn't lie to you about drinking alcohol = recipe for unhappy, unhealthy relationship.
And this is just one aspect of the frustration that living with an alcoholic will give you. Not sure what your financial situation looks like right now but my advice is to never share bank accounts. You continue to work, have your money and savings. Both contribute to rent and bills 50%.
All in all, if I were to roll back time to the 6 month period (which at that point, I also had just moved in with my alcoholic boyfriend) I would have left then knowing what I know now. 8 years later, My alcoholic husband is still an alcoholic.