Loyalty and Jealously

Is it that these 2 must coexist i.e. once one has loyalty then one is the object of jealousy or that they coexist like the two sides which make up a coin?

If it were that this were the case, this begs the question what is that jealousy and loyalty coexist to form? – just as the head and tail of a coin exist to form a coin.

Could the answer to this be: a relationship?