Friends (or the lack of them)

Okay so here goes nothing...
My name is Ella, and I'm 15.
Basically since I first arrived in New Zealand at the age of 7 I have been handed my friends by my parents (and don't get me wrong I totally didn't mind this at the time and they are all amazing people- also my parents didn't realise this hahah) but basically I have grown up with the same friends my whole life. When I first met them these girls were just gorgeous and complete innocent 7-8 year olds and I loved them. 
Now- and obviously being a teenager may not help much- they are all treating me differently. 
I have never been an extrovert like they all are and although I'm quite a confident person I am not really one to stand up for myself. Hence I tend to get picked on in my 'group'. 
Now I wouldn't call it bullying because I have seen way worse, but these girls  are just hurtful in different ways. Growing up with them I have always known that this day would come where I would basically just be left out so I have kind of been bracing it.
Anyway my real problem is the fact that they are being real bitches and discluding me completely in ways that I hate.
{quick disclaimer- I know you may just be like well tell them to fuck off and find some new friends but I swear if I could, I would have by now}.
It's just because these girls are more like family now- my parents best friends are their parents and as families we do EVERYTHING together and I literally mean it.
It is just getting to that point where I wish I had the courage to say something. 
Recently I have been on a hormonal treatment (like the pill) for my acne and one of the side affects is depression. 
I don't want to be the person to diagnose myself with something I have no idea about but I think the pill may not be helping my situation mentally.
I am so emotional all the time and almost every moment I have alone I think of this stuff and how worthless I feel and every day I get worse and worse. I cry a lot too which was something I never used to do in public.
I also have clinically diagnosed anxiety so that doesn't help. 
The other day I had a catch up with my only family friend who I feel I can talk to (not part of this 'group') and she had just been away with my bitchy friend (who I still love) and had conversations such as the fact that they know this is going on with me etc but none of them want to help me because they feel like if they try to include me they will be unincluded with me. I hate it because it basically just means that none of them can be fucked to sacrifice their social status in order to make me feel included. Ugh.
I know no one will probably read this but I think I just needed to let out a lot of internal angst. 
Basically I feel like I have no one who cares about me as much as I care about them which is surprisingly a lot (and I know it looks like I talk a lot of shit behind people's backs because of this but really I never do and that's why I needed to let this out).
When my friend (no.1)got a concussion I went over to her place the moment I found out and brought chocolates, movies and Instax film over to her.
For my friends (no.2) birthday I came over to her house at 6:30 in the morning with cake and 16 presents before I went to watch her netball game with her.
When I went to England for two weeks during my other friends birthday (no.3) I sent her flowers and chocolate all the way from England to her.
I am just so pissed off because I was taught that what goes around comes around and my friends would always say "don't do it for her if you know she wouldn't do it for you" but I do it anyway because I pretend that they would do it back to me. I think I have just come to the realisation that maybe none of my friends really love me as much as I do them and that maybe I don't deserve all the things back that I give them (not just talking about the presents).
Sorry for the blabber.
Ella X  
What seems like years ago^
I realise now that I was still left out then lol