Stephen's "love" is a curious one. Near the beginning of the book, his love for his mother gets him in trouble (love representing kissing his mother) and he ends up in a ditch because of it. Thus it could be said that love is a weakness for Stephen resulting in more hurt than strength, yet when he says he doesn't kiss his mother he still ends up in a ditch, leaving the reader in a grey area of interpretation.
Stephen also expresses his love for a girl named Emma. Throughtout the novel she becomes a symbol of unadulterated love in Stephen's life. Glimpses of her are mentioned throughout the novel, and he consistently imagines himself being with her. Yet because of their minimal interactions, it is difficult to decipher this love as a strength or a weakness. One could argue that she was just a distraction to Stephen yet at the same time, you could say she was motivation for Stephen, as she always imagines being with her as a reward to his devotion to the church.
Again I am left swimming in a pool of minimal evidence and my own biased opinions. Overall, I'd say that Joyce would welcome love, but say it is neither a strength nor a weakness, it is an emotion in life that is meant to be experienced. Your own self must be the one to decide whether it is a strength or a weakness.
