MDN has a good article on XML serialization and deserialisation in JavaScript, which covers all the options without having to resort to libraries such as jQuery.
Older versions of IE (pre-11) - and the current version of Opera Mini - have some limitations that may cause problems if you need to support them. Notably DOMParser.parseFromString
is missing: Check this.
If you really do want to convert to JavaScript objects rather than work with a DOM, probably what you want to look at is JXON. Here's the way.
Note that if you want to recreate your XML document from objects at any point, I'd recommend you convert it to a DOM and work directly with the DOM nodes. That way, when you reserialize it, the ordering of nodes will be preserved. If you go down the plain old JavaScript object route, ordering will be lost.