<human>: Condense the text into a few key points

So my gf and I got together this past February and have been in a long distance relationship since then but we were talking throughout December/January. She had this fuck buddy (let's call him Ab), whom she was interested in pursuing a relationship at the time but he wanted to stay poly. After she and I get together, Ab is texting and calling her, basically trying to win her back. She doesn't cut him off and indulges in talking to him but doesn't just straight up tell him that she doesn't want to be with him because she wants to be with me. Her reasoning is that she doesn't want to be mean to him. I don't think that's reasonable and I tell her I'm not comfortable with him, especially since she was doing things like inviting him over to events and getting high together. Because she doesn't change her behavior, I break up with her.

She tells me she's gonna change and not talk to him anymore so we get back together. Fast forward to today. 

Apparently Ab had contacted her 2 weeks ago, now "over it" and wanted to rekindle their friendship. They had a brief conversation and that's not really a big deal to me. What is a big deal to me is that today after work, she went to go see him at his workplace and then afterwards, they ended up smoking together. Her reasoning is that she wants to mend this friendship because she's not comfortable with how it ended and also that she wanted some weed (he was her weed dealer). 

I broke up with her just now because I see this as complete disrespect on her part towards me. I asked her if she realized that this would bother me and I wouldn't be alright with it and she said she knew but she felt like she really had to fix the relationship because he's "like family" to her.

I think this is complete bullshit but I'd like to get some other thoughts.
<bot>: I ask girlfriend not to hang out with ex-fuck buddy. 5 months later, she visits his workplace and smokes out with him. I'm pissed.