kvsgyrl4ever, You say you are confused - well, you sound confused... So at least you know what's up. First off, you have to remember the difference between loving someone and being in love with someone. It sounds to me like your relationship with your ex lasted for a significantly meaningful amount of time and therefore you two know each other particularly well. There's a degree of security that comes with that and any new relationship you engage in will lack that quality for some time. It sounds to me like you do in fact care a great deal for your ex at this point and also that you desire to have with your 'current' what you momentarily had (or thought/wish you had) with the ex. Take into consideration that your ex is probably in a similar position mentally and emotionally, weather he is aware of it or not.
You say that nothing romantic or sexual happens between you and your ex yet you've hung out on multiple occasions. Could you believe that regardless of romantic intimacy that he genuinely cares for you? That would be rare, you two still being real friends now after such a relationship... I wonder if the ex is making an effort to get back together and also under what circumstances you two met again after a year or so apart. Either way, everyone has their own issues, always. When you resolve your own issues you will find new ones have already cropped up - that's just a fact of life so don't go taking sabbaticals from relationships just because you're not perfect.
The way you describe your ex depicts the fact that he has some relatively significant issues of his own and based on your description I don't think the drinking is the real issue (the drinking is probably a result of his inability to efficiently work out his issues). Of course alcohol is addictive and also has a tendency to cloud the mind, so even if he did resolve his bigger issues he might still find himself habitually drinking excessively - which could be an issue in and of itself.
Honesty is key. It is good that you have been becoming more honest with your current boyfriend. About your ex though, it seems that you two are genuinely friends - correct me if I am mistaken. I wonder if your ex is honest with himself when he is alone and if so he still may get defensive and deny when someone such as you who knows him so well tells him something about himself that he does not see. That would make it hard for you to be honest with him about certain things and if you do not truly desire to be with him then perhaps it is not your place or to the benefit of whatever relationship you will have with him to get into such things, no matter how much you might care for him.
My advise to you kvsgyrl4ever is to really evaluate where you stand emotionally and mentally in regards to your relationships with these people you describe, and be completely honest with yourself. Nine months is typically a rocky period in relationships, so is 14, so is two and a half years, and 6yrs (I've been there a few times). It sounds like your current boyfriend can deal with such things that you are going through and is willing to be there for you in whatever capacity he is capable, that's not such a common thing to find in a man these days so don't give him up so quick. Also it seems your ex cares for you and would like to know you even if you aren't 'mates'... That's also not so common and you know each other so well - you could be good friends. In the end your heart will decide who you will be with and you won't be able to do anything about it anyway. Stay with the one you're with for as long as it works for you and don't burn any bridges or deceive either one of these significant people in your life. You're not "in love" with your current BF so I think you probably never were - so why did you hook up in the first place? Is that still working for you?