In-Laws Living with yopu?

I lived with my inlaws right after my wedding its because I got pregnant and my husband doesn't have a regular job so mostly its my mother in law who feeds us all. We have lived in the same roof for more than 3 years and my daughter was spoiled enough by her grandma. To cut this all short, eventhough we are living in the same roof I don't really feel close to them. Its like I still have reservations or I'm setting up boundaries. There are times also that I'm having my period and I'm not feeling well and my sister in law ticked me off great time! I want to hurl her a matter of curses but I didn't since I have lots of self control in myself, hehe. What I've done is I stayed away from her at that day because I dont want to cause more conflicts. Some things similar happened between me and my mother in law too but I also let it pass. I guess we have to be more careful when you are living with your in laws. Dont do things that you'll regret eventually because they are not just others, they are are your family too. We're not living with them right now but we are still helping each other until now especially on financial problems. I could consider our relationship now as civil, just normal. We're open with somethings but we don't meddle with each others affairs, I guess.