What is the logical relationship in wa-in kunti ... fa-ajmilī?

Imruʾ al-Qays: Address to Fāṭimah, Parting, and the Arrows of the Eyes (Verses 19–22)

• Since you have already left, I shall travel
• If you have resolved to leave, then part graciously
• If my heart obeys, wash the clothes
• Immediately wound your heart without any condition