The characters in the novel are very well-developed and relatable. Also, the writing style is quite captivating and makes for an immersive reading experience.
I'm not sure specifically as there could be many novels with this kind of title. It might be about a situation or a story that seems so wonderful or perfect that it's hard to believe it could be real.
There are so many novels out there, and without more context, it's impossible to say who the author of this 'too good to be true novel' might be. It could be a new writer trying to break into the market with a story that plays on the concept of things being deceptively good. Or it could be an established author exploring a different genre or theme.