To use a JS Framework or Not to Use

I tried to use various javascript frameworks in my HTML5 mobile app projects.

I ended up, again, using a custom SingleM-V-C structure along with jQuery Mobile for the rooting and the appearance.

The code seems well structured.

1. JQM's index.html: takes over the rooting and the views

2. Controllers Folder Classes: Handle the dom events(via jQuery) and request data from the models,

3. Models Folder classes: make the ajax or local db calls in order to fetch - send data.

4. Helpers Folder classes: assist with general class (like maths etc).

THE QUESTION:

Am I missing something?

Why should I use Backbone or AngularJS or anyother that seems to have a very complex steep understanding when I am trying to do something outside the normal behaviour?

Is there an MVC framework that works well with JQM?