[The Squatter of Amon Rûdh]

I think that what I find hard to accept about Aredhel is the fact that it isn't just her that pays dearly for her rather self-indulgent behaviour. She causes disaster for many through nothing more than whims and selfishness. She wasn't the only person who'd been cooped up in Gondolin for years, but because of her rank she was able to escape. She wanted that privilege, but when it came to living up to the responsibilities that went with it she was suddenly enamoured of the simple life. Granted, she's interesting, but for all the wrong reasons.
She is incapable of considering the consequences of her actions; she cares nothing for the welfare of the very people who provide her wealth, or even for her own family; and although she's not the sharpest tool in the box, she will not take anyone's advice. I cringe when I read her words to Turgon in The Silmarillion:

'I am your sister and not your servant, and beyond your bounds I will go as seems good to me. And if you grudge me an escort I will go alone.'

To my mind that reeks of adolescent petulance. It makes Turgon seem all the more dignified when he answers:

I grudge you nothing that I have. Yet I desire that none shall dwell beyond my walls who know the way hither; and if I trust you, my sister, others I trust less to keep guard on their tongues.

Anyway, that's enough ranting about what an idiot the White Lady of the Noldor was. On to whether or not she loved Eol: this wasn't exactly Middle-earth's greatest love-match, as we can see from the following:

It is not said that Aredhel was wholly unwilling, nor that her life in Nan Elmoth was hateful to her for many years.

Let's face it: that isn't exactly Romeo and Juliet. To me it looks like the spoiled little rich girl tying herself to the wrong kind of man to spite Daddy (or in this case, her brother, although the relationship seems remarkably similar). She comes to regret it, of course; but don't we always regret decisions that were made for the wrong reasons?
I think that this is why she is destroyed. Neither she nor Eol really loves the other, which causes disaster for both of them. Thus it is my belief that the relationship between Aredhel and Eol is as strong a criticism of loveless marriage as you will find in Tolkien's literature.

It is, however, ridiculous to blame one rather foolish character for an event as huge as the Fall of Gondolin. Aredhel is one of many people who, for differing reasons and with differing levels of culpability, bring down the Hidden City. I expect that this was one of Melkor's discordant themes, as the threads of wilfulness and self-interest that run through it seem so much in accord with his character.