Why is my friend acting like this?

he just wants to take his anger out on you and he needs someone to blame usually its the person closest to the hurt person outside of the family i would try and avoid him for now till hes in a better mood or just have it out with him. The same happend to my dad but i never took it out on anybody, to me he needs a good shaking, people lives are alot worser than his and hes not going to get better if he relises it and you wont better either if hes stays like that