A woman on Reddit is struggling to understand why her fiancé is taking his female best friend on a family trip instead of her.

The woman met her fiancé, "D," when she was in college, and he's known his female best friend, "S," since high school. He introduced the two women to each other early on in their relationship.

Last summer, the couple got engaged after years of dating, and the woman believes they "have a wonderful and deep love" with "very healthy communication."

"I always trusted D, so I never had a problem with their friendship. I have platonic male friends that I still keep in close contact with, so having an issue with it would be hypocritical in my eyes. I even developed a friendship with S over the years of us knowing each other, so getting to understand her on a personal level has also made me feel more secure in their closeness," she wrote.

Every spring break her fiancé and his family take a vacation, though she has yet to be invited because "only close friends or spouses are allowed to join in."

"I admittedly have felt a tad bit hurt by this in the past but I always let it go because it is not my family vacation, and I assumed he had no [say] in who he could bring along unless they met the requirements," she explained, adding that since they are now engaged, she thought she might finally get invited.

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"Friday night when he came home from work, he started to casually bring up how his family picked a certain beautiful East Coast beach as their destination for this year's family vacation ... Which, BTW, got me so excited because I thought he was about to segue into inviting me," she continued.

Instead, he mentioned he would be bringing S on his family vacation.

"I think he could see the confusion and devastation on my face, because he immediately started to say that he wanted to bring me but his family has known S for much longer than they know me, and that they love her so they don't mind paying for her to go on vacation with them," the woman added.

"I was genuinely so shocked and so hurt that I excused myself to the bedroom, locked the door, and sobbed my eyes out. The next morning, D came and spoke to me, saying he was sorry but that this vacation 'probably won't be that fun anyways since my teen cousins are coming' and that he would make it up to me by taking me out on a weekend trip sometime during the summer," she continued.

The woman "tried to explain to him that it hurts that he is putting another woman above me, his fiancée," and admitted she is starting to feel insecure in their relationship.

"I'm so confused on what to do or how to handle this situation. I want to respect his decision because I can appreciate that he can love and cherish another woman platonically, but at the same time I feel so betrayed that while he is on his family vacation with another woman," she concluded.

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In the comments, Reddit users urged the woman to reconsider her relationship with her fiancé.

"This would be an absolute deal-breaker for me. You are his fiancée, you are part of the FAMILY. If his family does not accept you, then that is a problem he needs to address, not just switch you out for someone they like more. How are they going to get to know you if you're not invited to things that would actually help them get to know you?!" one person wrote.

"To me, the problem is less that she is going, it's the fact that you've never been invited at all and I'm assuming you've been together at least two years. It's not really a family vacation if they want to invite anyone they deem a 'close friend.' The problem is 1. Your partner's parents do not want you there, and 2. Your partner is OK with that, even after you've gotten engaged. Obviously it's one thing to expect them to pay for you to go, but you aren't invited, period," another user chimed in.

"I'd tell him he can take her on that trip, but you'll be moving out and leaving his ring while they're gone, since you are clearly not the woman in his life," someone else commented.

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