The Star Wars Movies are a metaphor for drug addiction, Anakin is a junkie:

When we first meet Anakin Skywalker he is a rebellious youth that engages in reckless behaviors and who has grown up in a lower class environment. These are basically recognized as ideal conditions to lead someone into substance abuse. There's nothing he wants more than to find an escape from his life, and he does when Qui-Gon comes to Tatooine and introduces him to something new. In essence, Qui-Gon Jinn gives Anakin his first taste of a new substance: "The Force". Qui-Gon's gift provides him an escape from his life, and he is happy for the first time.

Now he's hanging out with Qui-Gon and Obi-Wan, who are two chill dudes that are also users. Their stuff is good, gives a nice feeling, and it's safe. They introduce Anakin to their buddy Yoda, who warns that Anakin may not be able to handle what they're trying to give him, but Qui-Gon doesn't listen.

When Anakin "uses" the force, it's amazing, and unlike anything he's ever felt before. But because of his background and how he was rushed into things, he gets a desire for more, which is when he meets Palpatine. Palpatine is a dealer that's got dangerous stuff. It's stronger than what Qui-Gon and Obi-Wan have given him, but it also has some nasty side effects.

Now, by the time Anakin starts really hanging out with Palpatine, Qui-Gon is gone, he's become best friends with Obi-Wan and Anakin has a new girlfriend, Padme. He loves Padme, but he also likes the way that Palpatine's stuff makes him feel. The rest of his friends don't like it though. Obi-Wan, Mace, Yoda, they all see the change taking place and they don't like it, but Padme loves him and refuses to see it.

As time goes on, he gets more and more into what Palpatine is selling him, until finally he goes too far. He does too much, and in his altered state he hurts Padme, which causes her death. His friends turn on him, but Palpatine's connections are good and he stops them all, either killing them or sending them into hiding. Unfortunately, addiction takes hold, and he finds that he cannot live without the drugs.

Years pass. Palpatine is still feeding him the drugs, and Anakin is still hopelessly addicted. But then something happens that causes a change. His old friend Obi-Wan shows up, and with him is Anakin's son. He knew that Padme had been pregnant, but he thought that his child had died with Padme. He has another confrontation with Obi-Wan about his drug use, and after that Obi-Wan leaves.

He starts trying to connect with his son. He hire's some people to find out more about the son he never knew, and the people he's hanging out with. At the same time he realizes that maybe Obi-Wan was right, and he tries to get clean (in case you're not following at this point, his addiction is represented by the suit, and during Empire Strikes Back, he is seen briefly trying to survive without the suit)

Anakin finally gets some one on one time with Luke, but Luke rejects him because of the drugs he's hooked on. Anakin is determined to make the connection with his son, and so he tries the only thing he knows to do, and takes him to Palpatine to get him hooked on the same stuff. But when Luke refuses, Palpatine tries to kill him. Anakin is given a choice, to stick with the drugs, or to save his son, and he chooses his son. He kills Palpatine, and he leaves with his son. He goes through a cleansing period, but finally he gets off the "dark side", and he finally goes back to his old friends, Obi-Wan and Yoda.