Yes. A lay Buddhist can date, have a girlfriend or boyfriend, marry, or remain single. Buddhism does not require laypeople to be celibate. The main ethical guideline is the third precept, usually understood as refraining from sexual misconduct.

Dating is not forbidden
Buddhist texts do not create a universal rule against romantic relationships. Household life is recognized as a normal path for lay followers, with teachings about duties between partners, parents, children, and friends.
Whether dating is formal, casual, or connected with marriage depends largely on culture and family expectations.
The third precept
Traditional explanations of sexual misconduct commonly include adultery, coercion, exploitation, and relationships that violate serious commitments or protected relationships.
Many modern Buddhist teachers also emphasize informed consent, honesty, respect, and the avoidance of manipulation or abuse.
Attachment and love are not identical
Buddhism warns against craving and possessive attachment, but this does not mean affection or commitment is forbidden. A caring relationship can cultivate generosity, patience, and compassion.
The challenge is to love without treating another person as property or as the sole source of permanent happiness.
Monastic celibacy
Monks and nuns who maintain full ordination live celibately. Their rules should not be applied automatically to lay Buddhists.
A layperson who wants a stricter period of celibacy may choose it voluntarily for retreat or spiritual discipline.
Relationships and Buddhist lay ethics
Buddhist scriptures do not provide one universal dating code for modern couples. Lay ethics is more often framed through precepts and qualities of conduct: avoiding sexual misconduct, deception, exploitation, intoxication that leads to harm, and actions driven by possessiveness or cruelty. A healthy relationship can also provide opportunities to practice generosity, patience, truthfulness, responsibility, and care.
Marriage customs in Buddhist societies are shaped by local culture as well as religion. A wedding may include monks chanting or offering blessings, family ceremonies, civil registration, or rituals inherited from regional tradition. These practices should not be mistaken for a single marriage law binding every Buddhist.
Attachment does not mean avoiding love
Buddhist criticism of attachment is sometimes misunderstood as a command to avoid affection. The issue is not caring for another person but grasping at them as a possession or expecting the relationship to remain permanently under one’s control. Compassionate love can recognize change while still involving commitment and responsibility.
For couples, this distinction can be practical: Buddhist ethics asks whether desire becomes coercion, jealousy, dishonesty, or harm. It does not require every lay practitioner to choose celibacy or withdraw from intimate relationships.
Practical answer
Having a girlfriend is compatible with lay Buddhist life. The ethical question is whether the relationship is honest, consensual, responsible, and free from exploitation and serious harm.