So now Buffy trusted Spike to take care of Dawn because he "had nothing better to do?" That's pitiful, but even if she did think that, the key phrase there is "Buffy trusted Spike."
what I meant was, you made a point of Spike having no soul - thats irrelevent, he was monster-impotent, he is no threat to Dawn, your example made it sound like Buffy trusted him while he was soulless, that isn't the case she trusted him while muzzled.
Trusting Spike to stay with the gang to "be the muscle" is, once again, trusting him. He could just as easily played kitten poker with the demons at Willy's bar, or,if he just had to have the violence associated with demon hunting, do it on his own. The Scoobies needed him, he didn't need them.
The scoobies didn't need him, who are you kidding? Willow could squash Spike with the wave of a hand at this point, the start of season 6 shows that Spike is feeling undervalued, becasue he isn't valued by anyone else.
And Buffy trusting him does not make him her closest friend, I said I see there is a friendship there, she does trust him, but trust doesn't immediately equal closest friend.
Spike had no purpose, he was caught between being conditioned to be good and still being a soulless monster who couldn't be a soulless monster, he needed the scoobies to give him a purpose.
Willow and Tara weren't the ones who kept Dawn safe from the motorcycle gang, and Xander and Giles weren't the ones who stayed there with her every night.
Eh dont forget they only left the house becasue "hiding" in the house wasn't Spikes style, and he fails at keeping her safe, he gets cornered and Dawn runs off, actually remember what happened in the show before claiming he kept Dawn safe, Spike failed and Dawn was lucky the newly resurrected Buffy showed up and actually kept her safe.
If telling secrets to strangers was Buffy's "thing," then she would have found a stranger to tell them to. Spike wasn't a stranger, strangers don't dream every night about saving someone, and the main reason that she told him about being in heaven was that she trusted him (there's that word again) to keep the information secret.
She did find a stranger, Spikes isn't a close friend, she couldn't tell her closest friends about heaven, just like how she opens up to Tara about coming back wrong, Tara is a friend but she isn't a close friend like telling Willow or Xander.
Buffy opening up to people outside her close circle is common, she begins to open up to the guidance counselor in season 2, she opens up to Spike, she opens up to Tara, and in season 7 she opens up to Holden Webster
And my definition of "closest friend" doesn't include throwing you out of your own home because they don't agree with what you want to do. At the very best, they should have been the ones to leave. It's not like there weren't plenty of vacant houses for them to choose from.
Again thats not actually what happened. Buffy says she wont stay in the house and watch them be led by Faith, and Dawn says if she can't get on board with Faith she has to leave, as they need to work as a team to win - Buffy decides she can't be a member of the team unless she leads so she leaves. She wasn't thrown out, she undervalued everyone and treated them like crap, she had to leave becasue she refused to be a member of the team.
At the time when Buffy needed support, encouragement, and just someone to hold her, it was Spike who was there, Spike who never stopped believing in her, and Spike, and Spike alone, who gave Buffy the strength and determination to go back to the vineyard and retrieve the Scythe. To me, that qualifies as "closest friend" quite well.
It isn't odd to you that Spikes advise of taking back the team is ignored, she doesn't listen to him, she doesn't even wake him up to go to the vineyard, becasue she got what she needed from him and she didn't need him. absolutely Buffy is Spikes closest friend, but Spike isn't Buffys, she constantly talks of how he's the second best fighter, but when going after caleb again she decides she doesn't need him. That speech in Touched shows how much Spike cares for Buffy, no one denies that, but Buffy doesn't care enough to bring him with her.
She continues not to care enough to contact him after he returns from the dead, she doesn't care to ask for help when Twilight turns up, she goes to Riley instead, then she doesn't care for his opinion on her getting an abortion, she turns to Dawn and Wood for that.