Q:

jQuery .next() Is Going Onto Incorect Div(S)

This basic snippet of code was written to change the classes of indexed divs. Specificaly the div with the class .primaryCategory . Now the function works great, it goes .next() and .prev() when you click on the correct arrow, but when you go next over 3 times (since there are only 3 divs present in this case) it moves on to the arrow divider. (as in .primaryCategory-leftArrow only, once it switches onto the divider (which its not supposed to) the left/previous arrow will not go to the previous anymore.
So basically what I am asking is how can I make it so that the next/right arrow will not go on to .primaryCategory-leftArrow
JavaScript / jQuery Code Snippet
$(".wrapper .primaryCategory-wrapper .primaryCategory-RightArrow").bind(eventtype, function(e) {
    if($("div.primaryCategory.primaryCategory-active").is(":last-child")){
        // do nothing
    }else {
        $("div.primaryCategory.primaryCategory-active").removeClass("primaryCategory-active").next().addClass("primaryCategory-active");
    }
});

$(".wrapper .primaryCategory-wrapper .primaryCategory-leftArrow").bind(eventtype, function(e) {
    if($("div.primaryCategory.primaryCategory-active").is(":first-child")){
        // do nothing
    }else {
        $("div.primaryCategory.primaryCategory-active").removeClass("primaryCategory-active").prev().addClass("primaryCategory-active");
    }
});

HTML CODE Snippet
        <div class="primaryCategory-wrapper">
            <!-- Single Primary Category -->
            <div class="primaryCategory">
                <!-- Primary Category Icon -->
                <img class="primaryCategory-icon" alt="primaryCategory" src="img/placeholder/primaryCategoryIcon-320x320.png">
                <!-- Primary Category Heading -->
                <h1>Lorium</h1>
            </div>
            <!-- Single Primary Category -->
            <div class="primaryCategory">
                <!-- Primary Category Icon -->
                <img class="primaryCategory-icon" alt="primaryCategory" src="img/placeholder/primaryCategoryIcon-320x320.png">
                <!-- Primary Category Heading -->
                <h1>Lorium</h1>
            </div>
            <!-- Single Primary Category -->
            <div class="primaryCategory">
                <!-- Primary Category Icon -->
                <img class="primaryCategory-icon" alt="primaryCategory" src="img/placeholder/primaryCategoryIcon-320x320.png">
                <!-- Primary Category Heading -->
                <h1>Lorium</h1>
            </div>
            <div class="primaryCategory-leftArrow"><!-- Left Primary Arrow (Mobile) --></div>
            <div class="primaryCategory-RightArrow"><!-- Right Primary Arrow (Mobile) --></div>
        </div>

A:

It's because your .primaryCategory-leftArrow and .primaryCategory-RightArrow is on the same parent element of your .primaryCategory, they are all siblings.
To fix this you can move your .primaryCategory-leftArrow and .primaryCategory-RightArrow from your .primaryCategory-wrapper.
Or you can specify a selector on your .next('selector'), like this:
$("div.primaryCategory.primaryCategory-active").removeClass("primaryCategory-active").next(".primaryCategory").addClass("primaryCategory-active");

This will only retrieve the next sibling with a primaryCategory class.

But clicking the right arrow more than 3 times will lose the active class
You need to add a condition to fix this, here is a better solution:
$(".primaryCategory-wrapper .primaryCategory-RightArrow").bind("click", function(e) {

    if(!$("div.primaryCategory.primaryCategory-active").is("div.primaryCategory:last")){
        $("div.primaryCategory.primaryCategory-active").removeClass("primaryCategory-active").next().addClass("primaryCategory-active");
    }
});

$(".primaryCategory-wrapper .primaryCategory-leftArrow").bind("click", function(e) {
    if(!$("div.primaryCategory.primaryCategory-active").is("div.primaryCategory:first")){
        $("div.primaryCategory.primaryCategory-active").removeClass("primaryCategory-active").prev().addClass("primaryCategory-active");
    }
});

And here is a fiddle

