^ The issue is that it was written badly. When Lana returned back in season 8 it didn't seem like it impacted him that much... he even went as far as saying that he accomplished a lot with her being away... and he pretty much told Chloe he couldn't put into words how he felt about Lois.
However I can sort of forgive it because Clark didn't realize his feelings for Lois and he wasn't in love with her yet... I believe Clark fell in love or realized he was in love when he thought Lois died in 8x22 ... that was the moment he cut off everyone and decided to get his training from Jor-El, when he saw Lois again in 9x01... that changed everything!

In the alternative timeline in 9x09 "Pandora" we saw what happened if Clark went on beliving that Lois had died, he was pretty much sad and said he died when Lois left... and gave away his dad's watch to save her life.



Um with Lois... as odd as this is, I felt that certain moments of season 7 showed Lois growing closer to Clark and having feelings towards him. When he was going to leave town in 7x02, in Siren when she had comfort in him being there. The awkward punch in 7x18. 8x01 when Clark said they were going to be partners and in front of him she doesn't seem pleased but when he leaves she smiles. So, I felt she was crushing on him in season 7... late season 7 and grew to love him during the first 3 episodes of season 8 when they became partners.