While I adore Lois (she's my fave female character to ever exist), I don't think you're being entirely fair to Clark. Yes, Clark should have treated Lois A LOT better in S8 but it was clear that Lois fell for Clark first. He didn't realize his feelings for her as quickly as she realized her feelings for him, because he was so deep in denial. Also Lois falling for Clark first was done deliberately so that there'd be a fresh take on the story and no one could say that Lois is really in love with Superman. I chalk the entire AoS up to some really terrible writing and the writer's own inability to let Clana end with dignity.

I think that Clark proved how much he loved Lois time and time again after he realized her loved her. Lois was the only person that Clark couldn't completely cut contact with after the whole "Clark Kent is dead" thing. When Lana left Clark in Requiem, he didn't go after her. He let her go. He didn't tell her "I died when you left" like he told Lois in Pandora. In Echo, Clark kept modifying the way that he asked Lois out so that she would say yes. He really wanted a date with her. Then in Crossfire he did everything he could to get back into her good graces after their fight in Roulette and he couldn't help himself from kissing her. In Pandora, he wouldn't let Lois sidestep the issue anymore and clearly told Lois that he wanted them to be a couple. In Disciple, Clark was the one doing all the PDAs (because Lois was being cautious about their relationship). In Persuasion, Clark was so scared about Lois leaving that he promised her they'd always be together. He knew she was under some kind of spell or hypnotic suggestion or something to that effect and that it would probably wear off but he couldn't stand the thought of her leaving and when he made that promise to her, you could see the dawning realization in his eyes that he meant what he said. In Escape, Clark planned a romantic getaway for the two of them and did his best to make everything perfect for them. In Charade, Clark came so close to telling Lois the truth but he didn't because she asked him not to. In Salvation, Clark couldn't leave Lois without kissing her goodbye.

Then in S10 we had Clark wanting to go after Lois and get her to come back but trusting her to come back to him on her own. He told her "I love you" in Homecoming and tried to recreate their interrupted dance in Bride. In Isis, he told her the truth about himself because he told her that he wants a future with her. She's the ONLY person he has ever told his secret to because he WANTED to. In Harvest, Clark gave Lois his Kryptonian journal and told her "You're the one. You always will be." In Luthor, Clark told Alt!Lois, "I can't live in a world where you don't love me. In Icarus, Clark planned a perfect proposal for Lois and when his plans didn't work out, he improvised in a shower of rose petals at their phone booth and it ended up being an even better proposal and he told Lois that she's "the woman I want to spend the rest of my life with." In Fortune, Clark couldn't stop thinking about Lois even when he was affected by Zatanna's champange induced mind whammy. In Booster, Clark was more worried about what people would think about Lois being with a klutzy Clark Kent then he was about how it made him look. In Finale, Clark told Lois that she's "not in his way. she's by his side" and just looks at his vows:

“I, Clark Kent, take you, Lois Lane, to be my companion, forever. With you by my side I will never be alone. Though the world sees a strong and independent woman, I’ve never known someone with such gentle grace and more pure heart. When I’ve been lost you’ve always been there to bring me back, so on this day, at this moment, I pledge the rest of my life to you. You’ve always believed in me, and I believe in you. When you believe in someone it’s not for a minute, or just for now, it’s forever.”

There is not a doubt in my mind that when Clark realized that he was in love with Lois that he committed himself to her fully. And that's not even including all the times Clark freaked out of his mind when Lois was in danger (Metallo, Rabid, Crossfire, Idol, Pandora, Disciple, Upgrade, Charade, Salvation, Lazarus, Supergirl, Isis, Harvest, Ambush, Abandoned, Icarus)

Now that's not to say that Clark is perfect and that he never messed up after that, but more often than not he tried to fix his mistakes and he let Lois know he was in their relationship 100%.