So Im sitting in this chair and a girl that i've been talking to alot lately comes and sits on the arm rest. I put my arm around her and were sitting there talking and then this other guy, one of my buddies. Comes and sits in the chair next to her and starts talking to her.. i hear him say, "Hes got his arm around you.. thats cute" and she said "itd be wierd if I told him to move it" so i just turn to them and say.. "well ill do that for you then" and I get up and leave and start talking to a different girl. Was this a good way of handling it? The main reason I decided to get up was because the day before we were in a big group and she was saying that that guy kept trying to wheel her and she keeps telling him to leave her alone. so I figured he would pretty much just snuff himself out, which eventually he did because she came back over and stood with me outside after about 10 minutes. What would you do in a situation like this? He kept coming over and trying to talk to her all night whenever she was with me

Don't get too stuck up on the idea on there's always a right and wrong in the world of pickup. There's always different ways to deal with a situation.

What you did was acceptable, you disqualified her over something she said, walked away willingly and social proof yourself by talking to other girls, which is a big DHV. She came back after that which is a major IOI, you should have further escalated.

Alternatively, you could have use that opportunity to chase frame. You could have replied, "I know right? How can I get my hands off her if she's obviously so into me??". Personally I would go for this method as you are displaying confidence and protecting her from being hit on by that guy.

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You only have 2 choices; either you cry and accept who you are, or get your ass out there and try to change yourself.

If she deliberately sat right beside you like that and let you put your arm around her you should have just been c/f. Grabbed her, pulled her onto your lap and said something cocky like "Is this too much?" and laughed it off. The guy wouldn't have been able to say anything and she would have loved it given you had that much of an attraction with her to begin with.

If given the option between an upfront and potentially awkward move with a guy she's comfortable with and some creep she wants to get away from what option do you think she'll go with? Creep is completely disarmed, wanders off and doesn't come back if you're upfront. You've just protected her, shown confidence and demonstrated how much better you are.