I'm engaged but am very attracted to someone else

I'm white, I would consider myself quite good looking. I work out at the gym so my body is toned, I have dark hair and like to look good too. I have a fiancee who is white she is pretty I love her, but I am attracted to my colleague ever since I met her. She is black but not African and is very attractive. I flirt a lot with her and really want her like physically and mentally, I even think about how pretty our babies would look if we had kids together. I my love fiancee but I really want this lady. I like her personality, skin color and I want her.

I don't know why I added our ethnicities but I did, sorry.
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+1 y
I've known my collegue for several years but the more I'm around her the more I want her.
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+1 y
Thank you to the mature answers given, if I had known this lady before I met my fiancee I would have chosen the latter in a heartbeat.
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+1 y
I have a week to decide what I'm going to do, break off my engagement and be with someone else that I want to spend my life with, who I think about rasing a family with, we understand each other, we get along, share the same friends, we both have feelings for each but are fighting it. I know she is attracted to me too, and I want more not just me flirting with her, I want her. This bad but I'm hoping that we both get pissed on a night out so I can f*** her and let her know how much I want her
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+1 y
Hello everyone! My ex did not take the news very well, I know she is still hurt. I'm still friends with our mutual friends, they have have been very supportive towards us. I am getting along very well with my new girlfriend. We are expecting our first child so I am over the moon.
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Hello everyone! Six more months to go before our baby is born, we are still in love and growing stronger each day in our relationship. Phenomenal support from our family, friends and well wishes.
I'm engaged but am very attracted to someone else
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