So my girlfriend wants to go back to dating (more to the story), am I taking this the right way?

so me and my girlfriend have been going out for 3 months and we been happy and got into no arguments. 3-4 weeks ago one of her old flames came back to town and tried to force himself back with her. telling her to" leave me I'm here now w/e" or some mess like that. she tells him off and says its" me and him now go away"

2 weeks after this she tells me that she wants to go back to dating and that "she thinks we moved too fast" I'm thinking in my head, WTF? but being a nice guy I try to be supportive and say OK. she tells me that I'm still her boo however

fast forward to the present (2 weeks later) her and him are together like all the time now while me and her have only seen each other once since this day. and are talking less and less.

im not planning on being a "fallout guy" for when this relationship obviously goes down the drain.(it fell apart the first time cause he is a liar) and he's spoiling her ATM like crazy, I honestly fells he's only doing this to see if he can steal her away and when after that pul the old "switcharoo" back to his old self. so I'm in the process of cutting all ties. cause I'm not sticking around any longer for this BS. plus my family and friends noticed that I changed as of late cause of this.

at time point I reached the point where I'm walking away no matter what. I'm just waiting to get back to her place one last time to get some of my stuff out safely before offically cut the ties and lock the door.

am I doing this the right way? I think I am and I think I'm being fair. I would have liked a friendship if this failed but at this point I don't even like her character anymore. so I'm just going to cut everything and go my way.

i finally understand why some guys take the "no guy friends" route with their GFS. at first I thought it was an insecure thing but now I see some chicks really can't handle this.

inputs and similar stories are all greatly asked for. thanks for reading this.
So my girlfriend wants to go back to dating (more to the story), am I taking this the right way?
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