When embedding quotes, I try to think of them as synonyms of sorts for what I'm trying to say. For example, instead of saying "ryaneverestsucks finds it difficult to embed quotes within his essays, as evident in when he says...", I could say: "ryaneverestsucks expresses his "diffcult[y]" with "embed[ing]" quotes "within...essays"." You don't necessarily have to do it this way though; the example you've provided is another way you could go about it, but I would rearrange your sentence structure to make it flow better. A different version could be: "May Callaghan's assertion that "...." signposts the beginning of Isobel's realisation that her mother finds an outlet in tormenting her."
With regard to examples, I could only find one
I for Isobel essay posted on the forums, located
here, but if you're looking for more general embeding quotes stuff, there's loads of high scoring sample essays
here.
Hope that helps.
