My music library makes no sense to anyone who looks at it closely. Mariza sits next to Within Temptation, who sits next to Metallica. I listen to almost everything, classical, jazz, Brazilian MPB, electronic, the full sprawl, but these are the two poles that pull hardest, and I have never felt any need to explain the jump between them.
Fado is saudade, is slow, is built almost entirely around loss and longing. Mariza can hold a single note until it feels like it is carrying the weight of everything you have ever missed. Metal is the opposite in nearly every sense: loud, fast, built on release rather than restraint. Within Temptation and Metallica do not ache quietly. They hit.
I do not listen to these because they resemble each other. I listen to them because they do not. Fado gives me a place to sit with what is slow and unresolved, the things you carry rather than fix. Metal gives me a place to push against something instead.
I have never needed the contrast to make sense. Fado holds the missing. Metal holds the fight. Most days, whether at a desk writing a paper or standing in front of a classroom, need both.