In the dating game fundamentally everybody needs the same thing (trust and emotional intimacy) but we're all very distractable and these distractions get in the way so we end up chasing what we want, what we find desirable, rather what love actually is. To overcome this people need to be aware of their distractable nature and intensely focus on what's actually important to them and communicate this to each other. In other words if you're with someone for any reason other than trust and emotional intimacy then they can't have that trust in you because you're just using them for what you find desirable.
Consider the classic sugar daddy relationship, older guy with money, young attractive woman, they both have reasons to desire each other however those desires also prevent them from trusting each other, they're not cooperating they're trading.
"I'll give you what you want but only if you give me what I want."
In an actual relationship both parties have a vested interest in what the other wants so there's no concern about whether a fair trade is occurring, no negotiating terms, both parties actively seek to improve the other's happiness because it improves their own.