I voted for Bernie, and have switched my support to Hillary. Although I'm young by most people's standards, I am old enough to have seen a couple election cycles and see the federal government at work. So here's a couple things to keep in mind.

Firstly, almost every politician is just as corrupt as Hillary, including Obama. This is how the game is played. If you demand for them to not have big money donors you will never be able to vote. Clinton, while not as good as Bernie, has made very strong promises to move us in the right direction. You can choose to not believe her, but considering every single Supreme Court justice nominated by a Democrat (including those nominated by Bill Clinton) voted against Citizen's United, there's no reason to believe Hillary's nominees will be any different.

Politicians react to what gets them votes. You know why the Democrats work so hard for issues important to the black community? Because 90% of black people vote for Democrats. Now that Hillary has come out so strongly in favor of Bernie's position she will see how his supporters react. If they vote for her in good numbers she will see that those are winning issues and make sure to do at least something she can point to in 2020. If Bernie supporters don't support her she'll say "it doesn't matter what I do, these people will never vote for me, so I'll focus on other issue". In 2008 Obama was against gay marriage, but said he was "evolving" on the issue. LGBT activists recognized he was asking for their support and he won the gay and lesbian vote 70-27. He then "evolved" into supporting gay marriage before the 2012 election.

One more thing on her honesty. In the 90's as first lady she pushed for universal healthcare, a position matching Bernie and far to the left of Obama. This should tell you that she isn't a Republican in disguise.

On the DNC being "in the palm of her hand", you have to realize the Democrats have been preparing for her to run for president for longer than you've been alive. In 2008 she ran and barely lost to Obama in the primaries. At this point she's getting to an age where 2016 is really her last chance, so the DNC has been making sure it happened. Other contenders recognized this and didn't enter (that's why Biden didn't run even though he would have had a good chance), so the DNC thought she wouldn't face a serious contender. Even when Bernie entered, he wasn't very well known, and early on polling showed Clinton up 30+ on him, so they didn't view him as a serious challenge. They just wanted the primary over with so they could focus on the general. Bernie ended up running a very good campaign and doing better than expected, but Clinton still won easily.

All that being said, if you want a short answer of who you should vote for, there's a very good reason Bernie has endorsed Hillary. He has worked with her for longer than you've been alive and knows her very well. He wouldn't have endorsed her if he thought she'd go back on her promises.