<human>: Can you provide a brief rundown of the text in within 3 sentences?

So this might be a little long but here we go. I have this girl who is one of my best friends and has been for a few years. When I moved back within two hours of her she was stoked so we could hang out more. She has three kids, but they aren't with her very often, but hanging out still means me and my fiancee driving the two hours to meet her. Even when we offer to pay for a train ticket to come and stay with us for a time, to help her out and whatnot it is too much trouble for her to bother. I even asked her to be the best man (woman) at my upcoming wedding, but she couldn't be bothered to try on dressed with my fiancee, and hasn't bothered to help in any way. The straw the broke the camel's back was this week. My 39th birthday was the 9th and my fiancee spent a month planning a surprise party for me. She offered to pay for my friends kids, and her tickets on a train AND their dinner but she was too busy being newly single. By the way she is 28. I am sure I am being a giant pussy, but I have lots of friends who ARE there for me and who offer help constantly without expecting me to always be the one giving. And bailing on me was bad, but not coming through for my fiancee really set me off. So what do I do? Tell her how I feel? Tel her I am growing up and need adults whoa re responsible? We are considering removing her from the wedding so we avoid drama and problems. What makes it worse is I love her kids and they look up to me. Should I keep the relationship alive so I dont hurt the kids?
<bot>: Best friend is a flake and almost ruined my 30th and might ruin my wedding. Should I tell her to piss off?