I feel like my best friend is replacing me :(?

[Daydreamx]

Hi im 13 and ive known this girl since i have been born (my mum met her mum before and she is a year older than me) we used to have this large group of friends when we were younger but some of the adults (parents of the kids) had an argument and we kinda split into two friendship groups. So it was then just me my sister and my best friend (who is also my sisters best friend, i know its strange we share one). So anyway, me and my friend have always gone to seperate schools and we used to be so close, wede do everything together. She doesnt live with her father and her mother has the same joint problem as my mum. But i feel that we are drifting slowley away . Shes always going out with her friends that she has at school, sleepovers, cinema and anything really. Shes always posting pics of them on facebook. However, when me and my sister try and make plans she is like, im too busy or ive got to clean the animals out (a very common escuse which is strange as they only have 2 rabbts). I feel that she is leaving us for her other friends. I dont want this to happen, ive never felt so close to someone. I mean, ive known her for about 13 years and i dont want to lose her. I often cry about this cause it upsets me so much. Also when she has friendship problems at school, she tends to lean on us more which makes me feel that im just her 'spare friend'. Lastly, im getting quite annoyed about her at the same time as she always tries to do better than me, if i get a nice dress, she always gets something more expensive or nicer. Also when i get something (like i get an ipod which i bought myself) she creates to her mum saying 'they got an ipod' and then complains about it.I know this cause her mum complains to my mum who tells me. And when my sister was like 'i might get a tablet' she was like 'no no no tablets are rubbish' but then she gets a tablet. Why is she doing this??? do you think that she is jelous ???? Im just so upset cause i feel that she is changing too much and does not like me anymore. What do i do???

[Tati-Ahna]

You need to end this friendship, it has run its course. She is not a very good friend and you can do much better. It's not your fault she is petty, jealous and superficial. Move on.

[Nick]

That sucks. It will be fine believe me just talk to her about it