involving in sil problem

I dont know why, i feel like i should vent today.

I m in the midst of a Navagraham type of family, no one concern about other very much, but to outside people they act like they are very close. They arrange for family tour which no one likes but all should go.
My FIL is a show case type person, every phone call attends during the tour, he says, "I m in xxx place, climate is very nice here". If he visits any place already, he wont include it to go, even his own sons didn't visit and eager to see the place. He just plan the no.of days for tour and place on his own, didn't concern about his other family members plan, their health to do travel. In family, all other people do what my fil wants, but internally they scold him about their inconvenience for this tour.

Mil-- her only world is cooking, house keeping. She acts like she is very afraid of everyone in the family. she wants to get pamper, but sadly non of her family members do that. she wont include (not even initiate) herself in her son and daughters problems, she wants them to open up their problems on their own to tell her, if they didnt, she tell to all neighbors and relatives that their sons are hiding something from her.
my mil didnt talk to me much and sometimes she insult me for not cooking upto her expectations, wearing salwars and many more. when me and my H is in inlaws house, She will not allow me to cook, act like she is doing all work before my H. Also, when we are there, my H wants me to accompany him where ever he goes, friends house, temple, shopping. Before time, my H calls his mom to prepare dinner for us and says we would be back at dinner time. I dont know, what happened after some time, nowadays he completing our dinner outside if we happened to be outside during evening. my H doesn't wants me to get involved in any decision making that happening in his house, so personally i just happy for that and do my work.

Whenever i did small mistakes like breaking glass tumbler, forgot to switch off light (not for hours, just for 2 mins) he scolds me and advice me. to say literally, he treats me, how we happen to stay in relative house during vacation, just like that my H made me feel like whenever we are in inlaws house. Never ever my H made me feel like it is also our house, even he sometimes acts like he is also a guest who is asking permission for each and everything he do in the house.

In recent days, the things didnt went well for my h and his dad. Also, my sil had a fight with my mil and indirect fight to fil. So the situation goes like their own children didnt act like what my PIL wants.

Before, they didnt concern about me, they just talk in phone only with my h. Mil used me to create sympathy for her before others, fil treat me like 'i m outsider'. Whenever i stayed in my inlaws without my husband, my mil makes me to go to my mom's house (personally i liked that).

During initial days of marriage, i worried about 'why they treating me like outsider?' After reading many threads and advises in indusladies, i felt happy that they are not interfering in my personal life. So, I also start to be like a guest, whenever i went to inlaws house.

Now, after my pil fights with their children, they are calling me and talk with me about their problems with my sil. They are blabbering about how their kids not doing as like they expected.

My sil and i having a good relationship, we had never ever asked others any personal questions and doesnt put our nose in others privacy. I gave her suggestions, only for the things she asked, apart from that we usually talk general things only.

Now my mil wants me use our relationship, to make me convince her(my sil) for what pil wants from her. But they didnt want my H to know this that i m involving in my sil's problem.

I just turn deaf ear, for what my mil asked. personally i felt, i should not involve in this, because definitely my sil will not like me to poke my nose in her personal problems. Also, i afraid that what if my mil dumped me back once our sil problems over. Along with that i would have a spoiled relationship with my sil as an added value.

Because of my past experience with them, I m afraid to believe their words. I dont want to be like a puppet in their hands where they are using me when they need and put in trash when they dont need.

I will get a "no-responsible dil" name from them, but inside my heart i m happy for not spoiled my relationship with my H and sil.

Now i m becoming a one of them(navagraha), who faces only my H.

"Do you think i m a selfish for not done for what they asked?" I had this small guilty inside me.