To the person who said that Caroline should "get over it" in regards to Damon, let me put this into perspective. Yes, Caroline decided to invite Damon into her home for a one-night stand as a pick-me-up (yes, women do that and, no, it does not make them automatically evil for enjoying sex and using it to make themselves feel better. If a man can do that without being judged then so can a woman, that is what real feminism is: being treated equal), but then Damon fed from her and when she naturally got scared he compelled her into doing his bidding. Not just as a bloodbag and a henchwoman/minion, but also in regards to sex. Am I the only one who vividly remembers the scene where Caroline wakes up in bed with Damon, clearly terrified, tries to tiptoe her way outside her room so he won't wake and she can escape. Damon wakes up, menaces her, and bites her (with the implication that he compels her to have sex with him). In regular human terms, this is a form of sexual slavery. Damon did the vamp equivalent of roofying Caroline and taking advantage of her. He even went as far as to threaten to kill Liz, Elena, and Bonnie if Caroline didn't comply. Hell, Caroline was trapped in HER OWN MIND when this happened, wanting her body to run but not being able to do anything about it.
For people who claim that Caroline meddled too much in the Damon/Elena thing that was going on in season 4, keep this in mind: if your best friend all of a sudden started dating a guy who roofied and raped you (and kept it up for weeks/months), what would your reaction be? Hell, even without the "WTF are you doing choosing to forgive my rapist and socializing with him like nothing happened" aspect, Caroline must've been terrified that eventually Damon would do to Elena the same thing he did to Caroline. It's a VALID fear. On top of that, Caroline correctly guesses that Elena is sired to Damon. Yeah, that would not give a rape-survivor triggers or flashbacks (note the sarcasm), especially one whose will and ability to say no was taken from her. And, oh look, the sire-bond makes it so that Damon (someone who DID abuse the power he had over a woman in a SEXUAL manner) can take away Elena's freewill and agency. But, no, Caroline's meddling, worry, or fear is not valid at all.
Truthfullly, when Caroline said "At least Ripper Stefan wasn't a manwhore" (paraphrase, I know) to Elena, all I could think of was that some staff writer wanted to address the fact that Damon raped Caroline. The original line probably was "Say what you will about Ripper Stefan, but at least he wasn't a rapist." But then they remembered that they want Damon to be a "hero" and so that part of him was swept under the rug.
About Caroline seeing Stefan as a saint. True, there IS a bias. Caroline isn't a perfect being and she's not supposed to be one. Us fans love her for her strengths AND her flaws. Can she be judgemental, yes. Can she be controlling, definitely. She, and the narrative, ACKNOWLEDGE this. She's a person with flaws and virtues just like anyone else. But again, these characteristics and her experiences make sense when they come together. Of course she's going to prefer Stefan over Damon. Even if Stefan didn't mentor her and protect her from Damon (twice: the vervain in Caroline's drink and when he stopped Damon from staking her), she would still rather Elena be with the brother that didn't sexually enslave her. Again, this makes sense according to Caroline's personal experiences.
Also, for those who claim that Caroline is a hypocrite for sleeping with Klaus after all he put Elena through: watch the season one scenes where Damon controls Caroline and then compare them to Klaus trying to get blood from Elena. I don't know about you, but the former is infinitely more creepy and disturbing than the latter. Hell, Klaus acts mostly like a professional around Elena compared to the way Damon treated Caroline. Also, the fact that Caroline has been forced (due to her friendship with Elena) to socialize with her rapist and act civil around him rather than get her pound of flesh is already too much to ask of someone. When you ask your friend to act nice with their ex-predator (and they comply due to their love of you), you don't have any room to throw rocks at them if they decide to hook up with your own enemy. On the subject of hypocrisy, at what point is it hypocrisy and when is it "Caroline changes her mind like all people do when they evolve and adapt to the life experiences they accumulate"?
So, no, I don't believe that Caroline was a shitty friend for "meddling."