Siddarth may treat aarti and sana like trash but that's because they deserve it from the way aarti acts like a doormat and how sana hits him one day and hugs him next day. Both sana and sid treat each other like trash. They both are using each other since sana likes paras and trying to make him jealous.
But the point of this topic is that Sid is very loyal to his friends. That is one thing I have notice about him from the start til the end, even when he was with Asim, his loyalty was with asim only. Even during task, when everyone is thinking how they will win the captain task for themselves, he is thinking how his team members would win and he always say who ever wins as long as it's my group members, he don't care. That is a team player he is.
It's good to be independent but when you can play with a team and want your team to win, team player mind. Even last task, he didn't play with everyone, he said you can eliminate me but he was playing for paras and mahira because he saw how everyone was against them and he said I am not going against my team members.