If you love your enemies, then you love God and neighbor. If you only love your friends and family, then you might not have the true virtue of love; you might only have the worldly version of love: affection for one’s own. True love of neighbor is seen in love for those who treat you badly, love for those who persecute you, love for those who annoy or displease you, love for those whose political and social views are contrary to your own, love for those who religious views are contrary to your own, love for those who are the outcasts of society, love for acquaintances and strangers, love for the needy (any kind of true need in body or in soul), and love for humanity as a whole.
Many people think that they have love, even though they are not in a state of grace. They love those who agree with them, who please them in some way, who are like themselves. Such a person only loves what he sees of himself in other persons; this is a disordered self-love, and not a selfless love of others. True love of neighbor is ordered under the love of God above all else. And since God is Truth, a person in a state of grace will love truth. And since God is Justice, a person in a state of grace will love justice. And since God is Mercy, a person in a state of grace will love mercy.
An adult who never knowingly chooses selfless acts of true detached spiritual love is not in a state of grace. He has at least committed the actual mortal sin of omission of not cooperating with actual grace in acts of true selfless love. A person who is not in a state of grace, either due to the lack of baptism, or due to the loss of that state by actual mortal sin, cannot perform any truly substantially selfless acts of love for God or neighbor. For he does not have habitual grace (sanctifying grace). He can cooperate with grace partially, haltingly, now and then. But if he were ever to cooperate fully with grace, that grace with his full cooperation would result in God bringing him into the state of grace, either for the first time, or again, by means of an act of at least implicit perfect contrition.
A person who knowingly chooses any selfless act of true detached spiritual love, in full cooperation with actual grace, is certainly in a state of grace. If he was not in a state of grace before such a substantial deed of selfless love, the grace that accompanies that deed allows him to be given the state of grace by God. If he was never baptized, then his selfless act of love in full cooperation with actual grace results in God bestowing on him sanctifying grace, through a non-formal Baptism (a Baptism of desire).
Pope Pius XII: “An act of love is sufficient for the adult to obtain sanctifying grace and to supply the lack of baptism….” [Address to Midwives]
Otherwise, if he was once baptized and in a state of grace, and he lost that state due to actual mortal sin, then his selfless act of love in full cooperation with actual grace constitutes an implicit act of perfect contrition, by which he is returned to the state of grace.
The only true spiritual love is the theological virtue of love. Sin and love are incompatible; they cannot coexist. In so far as you love God above all else, and love your neighbor as yourself, then to that same extent you do not sin. In so far as you lack the love of God and neighbor, then to that same extent you do sin. Love is light and sin is darkness. Shine the light of love and the darkness of sin is gone. Where did it go? Nowhere. Sin does not have existence or being; it is an absence. You can only rid your life of sin by being in a state of grace, which always includes the three theological virtues (love, faith, hope), the four moral virtues, and the three intellectual virtues, and by exercising these virtues, especially and above all else the virtue of love. When you love, you do not sin; and when you sin, you do not love. Although many persons will claim that they love, what they are referring to is at best an emotional love, and at worst a type of selfishness under the guise of love.
Many people who are living very sinful lives perceive a certain emptiness in their lives. But they do not know how to fill that emptiness. Sin is moral evil, and all evil is a deprivation of good. Moral evil is always a deprivation of the single threefold love of God, neighbor, self. Moral evil is a deprivation of love. Their lives are empty because they lack the theological virtue of love. They do not lack emotional love, or physical expressions of affection, or worldly relationships of various kinds (which are often confused with true love). They lack that type of love which alone is worthy to be called ‘love,’ the true spiritual selfless love of God and neighbor. That is why their lives feel empty. That is why all their attempts to fill that emptiness with false kinds of love ultimately fail. The emptiness that they perceive is a deprivation of true love, caused by their lack of the theological virtue of love, and caused by their many selfish sins. Unless they repent of their sins, receive the infused virtues of love, faith, hope, and choose acts of selfless love for other persons, they will continue to feel this emptiness, this darkness, this absence of the true love that is the light of truth — until they die and are sent to Hell, where they will have the deprivation of the light and love of God forever.