Temperance Brennan wasn't prepared for this. When he told her he'd met someone while he served his country in Afghanistan, she had no idea it would stir up feelings she'd long since tried to suppress. She wasn't prepared to watch him with her. She wasn't ready for Seeley Booth to be in her past, so watching him with Hannah made her heart ache. She wanted him desperately but in spite of herself she rationalised the relationship, labelling it platonic. It was a defence mechanism. She'd been hurt in the past, despite people assuming she was emotionally disconnected. It was easier for them to think that way. Things were less complicated if she went about life disguising her emotions.

This time, this place
Misused, mistakes
Too long, too late
Who was I to make you wait?

Just one chance
Just one breath
Just in case there's just one left
'Cause you know, you know, you know

Booth told her once that he loved her but she wasn't willing to take a chance on losing him. He was the gambler, she wasn't. She relied on scientific explanations for everything, love was no different, and she couldn't risk everything he was to her. He was much more than the man she loved, he was everything. But not pursuing that side of their relationship had been a mistake, and she knew that now.

That I love you
I have loved you all along
And I miss you
Been far away for far too long
I keep dreaming you'll be with me and you'll never go
Stop breathing if I don't see you anymore

It was too late to change her mind now that he'd found love somewhere else. All she could do was sit back and watch him move on with his life. But rationalising that in her mind didn't help the pain she felt in her chest.

She'd fought against her feelings for so long that it was normal for her – but to see Booth with someone else was forcing her to reassess her logical reasons why. They didn't seem to matter in the grand scheme of things. She truly loved Seeley, but she knew she'd missed her shot with him when he'd confessed his feelings and she'd shared her logical reason for not being with him.

She regretted that decision everyday now that she saw him with Hannah but it was too late – he loved her. He'd moved on – and she had to let him. But she wasn't ready to let him go, as much as she tried to deny it.

On my knees, I'll ask
Last chance for one last dance
'Cause with you, I'd withstand
All of hell to hold your hand
I'd give it all, I'd give for us
Give anything but I won't give up
'Cause you know, you know, you know

He was oblivious to her heartache as he cavorted with his girlfriend. He'd spent so much time loving the woman he affectionately called Bones that he had fell hard for the woman that had replaced her at his side. She wasn't Temperance, but despite that he loved her. It felt like much more than a rebound relationship, even though that's what it was. He barely thought about his partner when he was with her and that was enough for now.

That I love you
I have loved you all along
And I miss you
Been far away for far too long
I keep dreaming you'll be with me and you'll never go
Stop breathing if I don't see you anymore

At first his relationship was about proving he could move on. But as weeks turned into months, he started to imagine settling down with her. The only thing that stood in the way was his son, she had to meet his approval, and he wanted to make sure they were serious before he introduced the two.

His relationship with Temperance had been somewhat strained after his confession, but since he'd returned from Afghanistan they'd almost fallen back into the usual routine, and he thought it was going to be awkward between the three of them. It wasn't. His partner made an effort with Hannah and the two had actually become friends since she'd come LA. Still, he wasn't sure how he felt about that.

So far away
Been far away for far too long
So far away
Been far away for far too long
But you know, you know, you know

He stopped looking at Bones like he was waiting for the chance to let her know how he felt because he'd told her, so that regret he wouldn't have to carry around with him later. He wasn't expecting her response, even though he understood it. She was a scientist, she looked at things differently. She wasn't like other people who took chances. So he should have expected her reaction, even though he could swear he saw how she felt in her eyes every time she looked at him.

I wanted, I wanted you to stay
'Cause I needed, I need to hear you say
That I love you, I have loved you all along
And I forgive you

For being away for far too long
So keep breathing, 'cause I'm not leaving you anymore
Believe it, hold on to me and, never let me go
Keep breathing, 'cause I'm not leaving you anymore
Believe it, hold on to me and, never let me go
Keep breathing, hold on to me and, never let me go
Keep breathing, hold on to me and, never let me go

Temperance could still feel his body pressed against hers as he pulled her into a kiss. She could feel his lips dancing on hers as she fought to respond. She could feel his hands around her waist as he held onto her. But all those things were just a memory; there was nothing real to hold onto anymore. Booth had moved on, with Hannah, and somehow she had to do the same.