oh yes definitely, from the first moment we saw them together on-screen the chemistry was instant!
I've been re-watching Bones lately and I'm currently on season 2, I just watched the ep when Brennan broke up with Sully and he left to sail to the Caribbean, I love the fact that Brennan stayed, even though Sully wanted her to go with him even for just a year. Even Angela was trying to urge her to go with Sully for a year, but in the end she still refused to go, she told Sully she "wanted" to go but for some reason she couldn't, or she actually did NOT want to go after all, she didn't understand why she didn't want to go. I mean, as a forensic anthropologist she's travelled the world and has done archaeological digs and humanitarian work and studying different cultures in so many different countries all around the world, and often she would stay for months or years on a mission, so why wouldn't she go to the Caribbean for a year with Sully? There were some speculations as to why she didn't go, and then at the very end of the episode when Booth & Brennan were at the Royal Diner with Gordon Gordon, and he pointed out to them that the reason Brennan chose to stay was because of Booth
outwardly Brennan said she did not want to leave her work, and she thought that was the reason why she didn't want to go, but the REAL reason she didn't go was because she did not want to leave Booth
And I love their reactions to Gordon's revelations, they looked confused but also surprised, and this was way back in season 2, but I think Booth & Brennan fell in love with each other way before then
from the beginning Booth have always been extremely protective and supportive of Brennan, and even though on the surface it seemed like Booth was supportive of Brennan's relationship with Sully, but it was very obvious that he was jealous of their relationship. And somewhere along the way she subconsciously gradually fell in love with Booth too, and that's why she did not want to go to the Caribbean with Sully. And I think deep down Sully also saw the deep connection between Booth & Brennan and he had his suspicions, which he confirmed when he returned in S12, he said to Brennan "I knew you still wouldn't choose me", which proves that he had suspected that Brennan was in love with Booth and will always choose him, and in the end she did afterall
It took so long for B&B to realise their true feelings for each other
It's without a doubt that Booth is THE great love of Brennan's life, and vise versa, none of their other relationships even came close to the love and relationship that B&B have
even though they both separately have had significant relationships in the past, Booth with Rebecca and Hannah, and Brennan with Sully, but still there is no comparison, these relationships never even came close to being as powerful and significant as B&B!