«خَالَنِي أَصْدُقُهُ الْوُدَّ»
He imagined that I was offering him sincere affection.
Khāla here means to suppose or imagine. In “khālanī,” the suffix “-nī” is the first-person object—“he supposed me to be ...”. The following verbal clause states the content of that supposition.
The interest lies in the gap between what another person assumes and what the speaker claims is really going on. The poem presents an individual viewpoint, not an independently verified report.