My son has started communicating with me. Today he called up n said that he went out for lunch yesterday and his friends made him consume a cocktail which had beer which he was not knowing. I'm sure that my son is lying and he has consumed beer knowingly. Now I don't know how to deal with him. I just hate him. I sometimes feel what a failed mother I am.

We all know that in every step of life, there is a challenge for us. When a mother brings up her child, she realizes this all the more because of wanting the best for her child especially if she believes in the hereafter because she wants the best for her child there too.
Likewise, you are feeling a hatred out of love for your son. Its quite obvious that you are concerned that he should have the benefits of this world as well as earn the pleasure of Allah and benefit from the next world too. Therefore there's work to be done.
Play your role of being a concerned mother for your son. You will not be able to.make things better if you Nag or show hatred to him. Face the confrontation if he has resolved with you and wanting to keep good relations. Count this as the first step that at least your son has realized the fact that a mother is of great importance in his life by now talking to you.
It is very unlikely that a mother hates her child and even if you think it is so, deep down if you ask your self, you will find out that you love him and want him to be a great Muslim.
Your not wanting to live is not in your choice, for you are the property of Allah and He will decide that. Life is a free gift and we only live once in this world. Allah wants us to taste the pleasure of loving Him through all these tests like the one you're facing right now..
Be brave and try your best to be compassionate with your son. Slowly he will begin to trust you and appreciate your concerns.
You can arrange some good meetings with the people who can change your sons life by having healthy conversation and probably advising him on the side.
Mentally prepare yourself that this is going to be painstaking and a struggle. Remember Allah will surely give you the answer to your struggle and this is His principle for all the humankind whether they be believers or not. In the end, the beleivers will procure the most of benefits.
Read on.how to deal with the youth too and listen to some good lectures on that. They're so many available online.
inshAllah with time you will get your results if you're set on your goal and are steadfast in that.