First off, I don't believe that anyone on here can give you advice on how to feel about your father. Nobody in this forum is there with you when your father does this kind of thing, and as a result, we can't really get a fair insight into what's going on. You've mentioned a lot of things regarding your dad's drug problem, yet you've not mentioned anything about him getting any sort of help for it. From what you've said, I'm assuming your mum is fairly responsible - is it not possible for you talk to her and perhaps suggest some form of counseling for your dad? Drug problems are very difficult to admit to, and your dad is probably extremely embarrassed about talking about it to you, hence the excuses.
However, that being said, I don't believe you have any real solid evidence of a drug problem, although it definitely sounds like your dad is depressed. Again, as his child, he's probably extremely embarrassed to even think about talking to you about his problems.
I don't believe you truly hate your dad. However, I do believe you're very confused and naturally, you're also angry and frustrated with his behavior and how he's treating you and your family. The only advice I can really give you is to talk to your mum. Try and catch her alone and when she's not busy, and tell her what you've told us. That you don't like your dad's attitude and that you're worried.
Hopefully she can talk to him and over time, something might happen which will turn a light on his head, and will persuade him to get help. You cannot help people who are depressed or have an addiction, and I think that's the hardest thing to come to terms with if you're affected. I wish you the best of luck :)
-------
oh, she's a dreamer ♥
be the change you wish to see in the world
-------
currently studying in france