I'm just saying it how it is. Spark lost = I'm not attracted to you anymore. The reason for this generally is that you were a bit too soft, didn't make decisions, weren't very challenging and didn't really lead the relationship as a man should. It's kind of like how most men wouldn't be attracted to a masculine woman, we're attracted to femine women generally. Women are attracted to masculine men, when they don't have that there's just no attraction.
I don't buy that at all. Same with the 'alpha/beta' nonsense. Perhaps some relationships follow that formula to some extent, but in the real world peoples tastes are infinitely more nuanced. The same can be said for there reasoning to end relationships.
People are just different. My lady friends an absolute stunner yet chooses to go out with a middle of the road, average looking white dude with a B cup.
We don't even know anything about Rossi or his acquaintance, how on earth can we judge them at all? The only reason we can offer up advise is because we've probably objectively been through similar experiences.