Welcome to the site.
I am Dr. Kaushik and i believe i can help you with your problem.
First and foremost i will like to empathize with you since it is really tough to co-exist with an alcohol dependent person because alcohol invariably effects one's mental condition making him / her temperamental , dis-inhibited and abusive and most essentially oblivious to one's own priorities and duties in life as a result of which the quality of life of the person and of his spouse suffers gravely and pushes their life to regressive state.
I am sorry to say this but the exact same scenario can be seen in your situation where in although he is trying to make some efforts to overcome his addiction but it still seems like he has a long way to go and unfortunately he still feels that his addiction is not his but your problem which is a wrong mind set and is going to cost the relationship.
You see his rampant unprovoked mood swings that you have been observing are nothing but implications of the alcohol on his mood and cognition / thought process which speaks strongly about the level of his dependency.
So the reason behind my detailed explanation about the dis-advantages and intricacies involved in alcohol dependence and abuse is to provide you an insight about your standing and precarious future in this whole scenario because your boyfriend is still abusing alcohol albeit with some improvement in his intake but becoming sober still seems to be a far - fetched reality.
So i reckon that you have to take matters in your hand and give him an ultimatum that he either needs to go for rehabilitation / detoxification with complete abstinence to be attained immediately or else you shall start thinking of a life away from him since you are also getting sucked into this vicious cycle of his alcohol abuse which have already taken away 2 precious years from you and some more years are likely to get wasted if he still continues on life this.
All in all i am asking you to do a deep honest introspection about what have you gained from this relationship so far and whether he is going to do any better in future by turning around his life for good , if not for his sake but for your sake and for the longevity and survival of the relationship. After this is done you got to be strict with him and give him a time frame within which you expect him to clean up his act and give up on alcohol for life or else you will be forced to end this and concentrate on your own future.
Also i will like to mention that there is a drug called as Acamprol ( acamprosate) which is known to reduce alcohol cravings so you shall discuss this drug with his doctor for his use so as to bring a closure to his craving for this substance of abuse and this shall help him in giving up the alcohol addiction.
I hope this helps.
Wish you all the best.
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