I think its good to keep in mind its not simple to diagnose true alcoholism. It should be done by a medica professional . Ive heard people who actually fit into this group are smaller in number than is often suggested. Many others have various forms of alcohol abuse. Sometimes it can begin with stress, or sleep issues, self medicating o her issues like depression or some kind of emotional pain,
Early treatment is important no matter what the diagnosis. The concern I see is that with any unhealthy behabior , the fact it continues when there are negative consequences or weird things happening . With alcohol people are often in denial there is a problem. The substances in alcohol act to alter thinking so it makes a person more confused to really see what's going on. What appears logical to him might not appear logical to you or someone not drinking. Does that make sense?
So because of this its often important to get others involved like a medical doctor or therapist who can help examine behaviors and sort of help him begin to see cause and effect. We can do this to some extent but it gets tricky because of emotions, things might feel like a wife just complaining or over reacting l which might cause defensiveness and arguments. Its got to be discussed very carefully so he feels safe and can share and be open to discussing any concerns he might have.
Alanon is a good resource to put focus on yourself but won't help you help him. They do not believe this is possible. You will need to look outside that program if you want to do this. At least this is my experience.
Please do take care of your emotional health especially while pregnant. So much going on right now to deal with. Maybe a good time to consider family therapy and some of these concerns could be aired within those safe confines.