i think this really depends on a few things. is she trying to get close to you, or is she trying to get close to her ex THROUGH you? are her and your fiance on friendly terms? was it a bad breakup that still has some open wounds? is your fiance still friends with her? how does he feel about you being friends with her? think about all of this. but to me, it sounds like she is just trying to be friends. i mean, she's getting married so unless she's a total psycho, i doubt she still harbors any feelings for you fiance. since you two are related, she might honestly just want to get to know her cousin better, and get the kids together to get to know their cousins. so unless your fiance has a serious problem with it, or you get the vibe she's trying to get to him through you, i'd say go for it. be friends. she sounds nice. give it a chance.
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I've never really saw any reason to be buddy-buddy with any of my ex's ex's. Quite frankly, I don't see a reason why they would even have contact, unless they had a child together. But this sounds innocent, just as long as her intentions are to stay faithful to her soon-to-be husband; then I wouldn't have a problem with it. It seems as if she has a life of her own. But I definitely would not tell her any of my business, until she got some of her own. Meaning, she's married, got her family started, and appears happy. If you're not sure, play it smart. Don't tell her any of your fiances' and your business. But you can vent or get advice about other topics. My rule has always been this: "only get advice from a person on areas of life, you feel they're doing well in." That means if she hits her child, she is not someone you would ask how to discipline your child, so that they'd get your point. One thing for sure is, you don't have to like her, but you at the very least, have to be cordial with her; at least for the sake of your child witnessing you being an adult. But it really seems like she wants to be grown about the whole thing.
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