Technically, that's not true. Not even in the old Jedi Order. Jedi were not allowed possessions. The only thing that even came close were their lightsabers. The Jedi Order discouraged love and relationships because possessiveness potentially grew from those things, which led to greed, so on and so forth. But certain Jedi were allowed, or even required to marry. Jedi Master Ki Adi Mundi was one. His race had a low birthrate, so by his planet's laws, he was required to marry and procreate, and so he did.