I mean no disrespect but the fact that you would prefer to stay out of the house at a time when your family needs you is telling of your immaturity. Rather than seek escape for yourself, wouldn’t it be nice if you could come home and contribute in a good way to the situation?
Granted you are working and I’m sure get tired at your job, but your mother has no such possible escape from the chaos at home. She is immersed in it 24 hours a day. Have a heart.
As well as the stresses of the impending wedding, which takes its toll on any family, your parents are dealing with an enormous number of house guests. That is never a walk in the clouds.
It’s only for a couple of weeks.
In terms of dealing with the stress…I don’t know how religious you are but for me namaz works…it acts like meditation and gives me the patience that I need to deal with stuff. I ask for Allah’s mercy and beg him to give me strength and perseverance.
Remind yourself that this is a very temporary situation. Things will improve as soon as the guests leave and your mother has less stress.