I helped you find her a diamond ring
You made me try it on and everything
Tomorrow you'll both say "I do"
And I'll be there 'cause that's what best friends do

She couldn't help but be supportive of Oliver and Felicity. If he was happy, well, she was happy for him. Wasn't she? What other choice did she have? So, when he asked her to go ring shopping, even though it felt like someone'd punched her in the gut, she said yes. She'd always imagined he'd buy her a ring one day, but Lord knows nothing ever goes the way she plans it. She'd be there at his wedding, sure, but she wouldn't be the one in white. And she'd have to accept that, because that's what best friends do, and she'd rather be his best friend than his nothing at all.

I should win an Oscar
Best actress in a show
You always see me smiling
Little do you know

"Do you like this one?" he asked her, completely oblivious. It was perfect, and she said so, smiling brightly. She hadn't known a heart could break more than one, but Ollie's put her through the wringer so many times it just kept splintering into smaller and smaller pieces. She didn't know how it was possible to still love him after all this heart break, but she was starting to think she was a glutton for punishment, just like her old man. She hated to admit it, but she loved this boy, despite it all.

I'm a liar, I'm a liar
The biggest liar in the world
I'm crying, I'm crying
Like I've never cried before

Nobody seemed to see through the facade, but Thea. Diggle whole-heartedly believed she was over him, Felicity thought they were gal pals, and Ollie, well Ollie fell for it the most of all. Only Thea knew the real truth, and that was just because it was hard to hide all the tears from someone she spent nearly 100% of her time with. At the base, at home, the littler Queen was everywhere she were, and the other girl knew all the signs. Thea was missing Roy the same way Laurel was missing Oliver; there was no real reason for any separation, it existed purely to torture them both.

I know you always heard me say
You'll meet the perfect girl one day
The night you called and told me the news
I said that I couldn't be more thrilled for you

"I'm really glad that you found Felicity, and I hope you find your way back to her. And Ollie, I know that I'm not the love of your life, but you will always the love of mine."