I have been trying to wrap my head around the idea that something we desire so much and that looks so good could be so bad for us.

Based on a concept from the Ohr Hatzafun and from the hakdamah of Shaarei Yosher (worth buying the entire sefer for), I came up with this:

The ultimate good that we want to be part of is Hashem's chesed. The way He does chesed is not by having everyone share everything - communist style - but by giving each person his own g'vul. Hence, the Torah largely consists of gedarim - this is ossur; this very similar thing is mutar.

Lust means wanting to be without boundaries - to see all and be connected with all. Unlike Hashem, however, we are not able to be completely selfless, but will take more for ourselves (look at the former USSR). The only way to solve this conflict is to feel that we are part of a greater whole - one Klal that has many parts, each with its own identity and possessions.

The Gemora says that if one wants to be a tzaddik - he can either learn Berachos - acknowledging that all comes from Hashem - or N'zikin - acknowledging that we all have our own boundaries.

True ahava can only come when I realize that I have mine and you have yours, and we are both children of Hashem, and the separation is the greatest expression of His love. Trying to have it all means that there is no space for anyone else.