The "feeling" of love is largely out of your control; you can no more choose to feel love for someone without an action than you can choose to feel pain, hunger, or misery. The only love over which you have any control is love as an action: choosing to include someone in your life.
In that sense, the idea of "Unconditional Love" is responsible for an enormous amount of destructive, abusive, and codependent behavior. It should be abandoned.
Love must be conditional. The conditions, however, don't include understanding or agreeing with someone. It's just one condition: that the other person does not mentally, emotionally, or physically abuse you. If a person cannot abide by that one simple rule, you may want feel love for them, but you must not keep them in your life (love as an action) or you will suffer on their behalf.
In an emotional sense, "unconditional love" is meaningless because you can't choose to feel love. And in an action-verb sense, love must have that one condition. Otherwise, you are positioning yourself as a martyr, suffering endlessly for the sins of someone else. And as far as I know, in the Judeo-Christian tradition, only One Man was ever required to do that.
Even this atheist can tell you putting yourself in that position is probably a bad idea.