Answer:
Trust equility.
Explanation:
Whats's missing here is trust by Zach, because his already imagine that his boyfriend is cheating on him without knowing it for sure. On the other hand, Zach's boyfriend trust him, because he's giving Zach space to spend with his friends without question his honesty, like Zach did. Therefore, the balance here is missing, becoming in a not healthy relationship, the trust equality is not present here.
In addition, a healthy relationship is trust based, and having individual space, because each person have own friendships. Most of the time people think that couples have to stay together always, which it's not true, because they are individuals before becoming a couple. This the reason why some couples feel stuck and drowned.
