I don't think they were "in love" during Gadchiroli days but they had some weird understanding
They had some connection during GC days. Virat felt restless when Sai was in hide out & went there in disguise. Sai was upset when he didn’t show up to pick her up from hospital after her discharge when she tried to commit suicide.
That’s why even during intital days of deal marriage they were very comfortable with eo. They did not mind sharing the bed. Sinhagad killa came later.