Advice please?

I would start by confiding in this family, telling them how hard it has been for you. Maybe they can give you some insights into French culture that will be helpful in turning things around.

You're going to run into cliquishness where ever you go to school. You have an incredible opportunity to explore another culture and language, with a supportive family going out of their way to include you and arrange special opportunities for you. That far outweighs any ostracism you may feel at school. Their loss that they don't want to take advantage of the opportunity to learn more about another culture and language from you.

The decision is always yours to make and you should only do whatever feels is best, but if your willing be fully committed to what you started and is fully prepared to deal with any and all possible difficulties/inconveniences, then stay. If not, I recommend you go home.

You have toughed it out for seven months. You have only THREE months left. Why don't you ask the family with whom you are staying if there are any counselors at the school you attend. Sometimes you just need to talk to someone for perspective.

The counselor might even find you a buddy to hang out with for the time remaining.

When I was facing hard times, (and I faced a lot of them), I used to say to myself, "I could stand on my head for three months.", (...or four...or whatever time I had to endure).

I know you want to go home and your Mum wants you home...but isn't that like extending your childhood?

Your little story here is filled with holes. You chose an exchange program in a country where you only just "now" speak the native language? 0.0 people in school talk to you, no students, no teachers, yet your exchange family is "amazing," but have done nothing to address your situation? You have felt so excluded for so long it now feels normal to you, yet you broke down when you visited with your sisters... last week, but you've never said anything to your "amazing" exchange family... in 7 months? Presumably, they know nothing of your troubles and they just plan things for you to do with them even though they have 0.0 idea what you are going through and you have no intention of telling them... unless you decide to just go home?

Did you just wake up one morning and declare, "I'm going to be an exchange student" without considering what being an exchange student is like? Are you even in school? Seriously...?

Tough times never last, but Tough People do !

When life puts you in tough situations don't say "why me", just say "Try me".

“You must do the thing you think you cannot do.” ~Eleanor Roosevelt

Once you start working on something, don't be afraid of failure and don't abandon it. People who work sincerely are the happiest. - Chanakya

You might regret it later if you leave it in between.

“Whatever you think that you will be. if you think yourself weak, weak you will be; if you think yourself strong, strong you will be” - Swami Vivekananda

Best Wishes :)

One of my good friends in University moved from Hong Kong to the United States when she was 15 and she was still struggling a lot with her English at a university level at 18, she had her boyfriend and two friends. And even though I switched uni's I stayed in touch and came to her graduation. She said she often felt excluded from everyone else besides us and was really homesick at times. I think it's good to let your family know what's going on and that it's been rough.

Can't tell you what you should do moving forward, that's up to you.

Tough it out. Stay and probably things will change.
This will prepare you for life, things will be bad and things will be good. You cannot run back to your family as soon as something wrong happens.

That's really a rough call to make. Your family sounds great, like they really want to take care of you and make sure you're alright. If staying there would make you continue to feel bad, they don't want that.
But try something different. While in school, worry not about others. Be kind if anybody wants to talk to you, but try to focus more on school work or something. Then after school, join some school clubs or go to fun places around town. Even just while trying to shop, try to strike up some conversations with the employees or others. In any case, shake up your routine. Give it another week or two and see how you feel about it then.

Maybe speak with a counselor or therapist? And let your family know you are struggling.

Stick it out. You're already over half way through the year now - so it could be something that you come to regret if you go home now because of the fact that school is a difficult time for you.

It's also good practice for when you leave school and get a job. These same issues happen at work, too - and you can't just pack your stuff and go home then like you can now.

you should go. it's what you wanna do.

Hang in there. It is nearly mid- April. Not far til June. Teenagers can be hard especially if you are foreign..You are a bit homesick. Only natural. Finish your time there. Then return home knowing your strength.

Higher education is not something we do to make friends, we get into it and stay because we want the knowledge and/or the chance at a better job. It does hurt when no one talks to you though, especially if you have a specific class that you need to sit in every time to the point where you know everyone. Personally, I just cherry pick lessons I need to attend to do well at school, the rest I do from home.

@dancingtongue Thank you but I'm worried that it will destroy my mental health if I stay and the majority of the time I'm at school

Definitely stay. You made a commitment, keep it

May I guess the country you come from ?🙂

Have you taken any initiative to talk to anyone?

Human sacrifice. If I've learned anything in my time here on sw, that's always the answer.

Tell them you are going to leave. If they ask that you stay, ask them why they choose to exclude you.