Love can be unselfish, in the sense of being benevolent and generous, without being selfless.
Be unselfish. That is the first and final commandment for those who would be useful and happy in their usefulness. If you think of yourself only, you cannot develop because you are choking the source of development, which is spiritual expansion through thought for others.
The moralist is the person who tells people that they ought to be unselfish, when they still feel like egos, and his efforts are always and invariably futile.