The Monster's Loose

I'm astounded that no one has taken this yet. Anyway, the song seems to be a brilliant take that towards a friend's particularly horrid ex.

"You're absolutely so much better than her"

That's pretty common for a friend to tell someone after a breakup, especially if the relationship was toxic.

"A second thought is too much,Is two too many?"

Yes, yes it is. This line seems to be a cautionary to try not to think about the ex.

"She's a fact of life, but never mind/get away, away from someone kind"

It basically says "Yes, you dated that person, but now you can spend time with people who will treat you right and you don't have to worry."

"Such a vain iconoclaster, A racketeer who never fears"

Okay, I would hate to make Mark Mulcahy angry. An iconoclast is a person who attacks cherished beliefs or institutions, in this case, the ex was a hateful nag that attacked everything the listener cherished and held near and dear to their heart (i.e. passions, hobbies, friends/families) To add insult to injury, the singer refers to the ex as a racketeer which is a person who engages in in dishonest and fraudulent business dealings. In short, the ex is a deceitful person who criticized the poor soul at any opportunity they could get.

"The lines of the news of his departure was met with a Cheshire Grin (Oh, better get away from here)"

This could be two things. A.) The context of a big smile. That horrible person is finally gone and now that person can have a smile that touches their eyes, especially since they're free to leave. B.) The ex is like a Cheshire cat in that they're catty and are trying to pull a trick, much like the Cheshire Cat in Alice in Wonderland, which could change the meaning to a word of caution "Better get away from here"

"The monster's loose/You're luckier than you know, The one that got away/He's gone, she's gone."

They've cut their ex loose and they're lucky for it. Although the 2nd part is kind of a contradiction, it makes sense, especially in long term relationships. It's common for people to feel like their ex was "the one that got away" because that person still holds their focus because that was their most recent ex, and those feelings are all the stronger if the relationship was a long (or relatively) long one.

"A great big celebration, seems more in order And it's a great big revelation,That should pull the plug on the whole thing, (I'm so thrilled for you, really)"

A common thing for a good friend to do is take their buddy out somewhere, especially if they've had a breakup or other generally tough situation. They sit and talk about it, that can really help someone get over their hurt and anger. Of course, the singer is thrilled for their friend's quality of life being better again.

"The monster's loose,You're luckier than you know, The one that got away, He's gone, she's gone"

The meaning's still the same, but I'd like to note that there is hardly ever just one conversation about an ex. In this case, the chorus is also like a reminder of the same conversation, much like in real life.

"It's so easy to be fooled by such a crackerjack,There's a weak signal/ Now here's all you have to know, just let the monster go."

It seems to be a final cautionary to the listener, a crackerjack is someone that is exceptionally good at what they do, in this case, just a warning that the listener's ex is very good at being manipulative and for them to just ignore this person now that they've broken up since all that's left is a weak connection between the two. A weak signal is a reason for hanging up the phone, or in this case hanging up the phone and "just let the monster go".