"
Forget all we said the night
No it doesn't even matter
Cause we both got split in two
If you could spare an hour or so
We'll go for the lunch down by the river
We could really talk it through
So he's telling her to just forget what happened when they fought cause it doesn't matter anymore because both of them miss each other and that they split up because of it and he's asking her if she could just give him some time they'll go have lunch down by the river and talk about what happened and try to work it out because they don't feel complete without each other. The reason why they feel like they both only have half a heart.