Oliver left the foundry without knowing where he wanted to go. He needed to be alone.
Fighting Slade again had taken its toll on Oliver. While Slade was obviously a physical threat, the way he could get into Oliver's head always bothered him.
Oliver may have beat him physically, but Slade had gotten into his head again. While they were fighting after Felicity had left, Slade said something that made him question everything.
Without consciously deciding to, Oliver went to the chemical plant where he had defeated Slade just a few months ago. He needed to get his head straight and maybe being here would help him do that.
"You'll never be able to protect her. You'll never keep her out of harm's way. She will die because of you, kid."
Oliver thought back to Slade's words and felt his fingernails dig into his palms. He hated that he let Slade get to him like this, but he knew Slade was right. He knew Felicity would always be in danger because of him. As long as he was the Arrow, anyone he loved or cared about would be in danger.
Oliver stayed at the plant for hours, just sitting there and thinking. He thought about Felicity, Diggle, Thea, his mother, and even Tommy. All the people he had allowed to be in his life since he got back from the island and two of them were already dead. His mother died because of him; because of Slade. Tommy died because he couldn't stop Malcolm. Who would kill Felicity and Diggle because of him? Who would kill Thea?
Oliver's thoughts plagued him for hours and his head had begun hurting from thinking so hard.
Would he be able to give up these people in his life to keep them safe? Or would he try to protect them, even if it meant he could fail? Would they let him push them away?
Oliver heard footsteps approaching and he immediately went still. No one knew where he was and he had shut his phone off hours ago. As the footsteps got closer, he readied himself to attack whoever was approaching him.
"Oliver?" His breath caught in his throat as he heard Felicity's small voice calling for him. Was he hearing things? There was no way Felicity knew he was there. She couldn't track his phone when it was off.
He peeked around the corner to see if he had officially lost his mind, but he released the breath he had been holding when he saw Felicity feet away from where he was, looking upset and confused.
"Felicity. What are you doing here? How did you-"
"I have a tracker on your phone. It works even when it's off." Felicity said, cutting him off.
Oliver looked at her and realized her cheeks were red from crying and she looked exhausted. He approached her slowly and stopped when he was only a breath away from her.
"Felicity…" He started, but he wasn't sure what to say. He knows the way he left her in the foundry earlier had upset her.
"Listen, Oliver. If you don't want to be with me just tell me. I can handle it. You either want to be with me or you don't. It's simple." She told him, and when she finished, Oliver could see the tears that were threatening to fall from her eyes.
He took a deep breath and raised his hand to rest on her shoulder and saw her visibly relax the way she always did when he did that. Oliver knew it always comforted her and, if he were honest with himself, it comforted him too. He probably needed it at that moment as much as she did.
"It's not that, Felicity. I want to be with you, I do, but what if something happens to you because of me? Slade said-"
"I don't care what Slade said! Is that what this is about? He told you he would hurt me?" Felicity said, cutting him off and stepping even closer to him. He could feel the heat coming off of her as she put her hand on his arm and looked him in the eyes. "Nothing is going to happen to me, Oliver. You deserve to be happy. I deserve to be happy. We deserve to be happy. Together. You will always beat Slade. Don't let him get in your head. I believe in you."
Oliver smiled as he saw Felicity realize she had told him that the last time he felt he wouldn't defeat Slade. Last time it was about the physical aspect of beating him. This time it was about the emotional battle it took to beat Slade.
"Oliver. You need to believe in yourself. I can tell you I believe in you all day, but it won't change anything if you don't believe in yourself." Felicity squeezed his arm when she finished to show she would be there for him and Oliver got the message loud and clear.
Oliver put his hand on the side of Felicity's face, cupping her cheek, and he leaned down to kiss her. Just as he was about to cover her mouth with his, Felicity being typical Felicity said "As much as I'd love to make out with you right now, can we do this somewhere else? This place reminds me of Slade and I don't want to think about him while I'm kissing you."
Oliver smiled and placed a lingering kiss on her lips before taking her hand and leaving the chemical plant, and Slade, behind.