Losing your best friends to marriage

When they started dating their SOS (at different times mind you) it was pretty much the same as it was before. I moved two hours away for a year but we were all still really close and when I moved back nothing really changed. 

When best friend 1 got engaged (while I was 2 hours away) we were all so happy! I helped plan the bridal shower and General wedding stuff. I wasn't in the wedding just because life stuff happened. I couldn't even attend the wedding because I had just had surgery. Then almost over night after she got married she disappeared. I chalked it up to her being a newly wed and once things settled down she would be more available. I new things where going to change however it's been almost a year and a half and she still doesn't have time for anyone but her husband. 

Now best friend 2 and I have been friends for years! Our relationship had its rocky parts but overall we have been solid. Then she started dating her now husband - who was also a really good friend of mine - so we all hung out! It was great and fun! Then she got engaged and things changed. She started not having time for anyone. All her other single friends were in the same boat as I was in. But I texted her saying if she needed help with her wedding I would help her. None of her bride's maids where helping her. I helped her at every turn and even listened to her bitch about her maid of honor not doing jack shit. And I made gifts for the bride's maids and everything. Now when her sister dropped out of the wedding party because she was supposed to give birth that day, I thought she would ask me to fill in since I had been there for her this entire time. Nope! Who does she ask? This girl who she just started being friends with in the last year who was dating her now husband's friend. After she got married I haven't heard from her. She has no time to even grab coffee. 

Is this normal for when your friends to get married they forget they have friends outside of their husbands ? Sorry for this being so long.