If there are some relatives you know will always annoy you, try to avoid seeing them or being around them if possible.  If you cannot avoid them entirely, just try to spend as little time as possible with them.  If you have to spend time with them, speak with them as little as possible. If you have to be around your super-annoying relatives, try ignoring them when they say something to you, when they do something annoying, or just walk away. Ignoring annoying behaviors (and there are many) is a good way to rise above the crowd and not to engage, even if they are annoying you. Solitary activities can build a wall of insulation around you when you are in a place where there are annoying relatives.  Go into the kitchen, or a bedroom, just to get away.  Wear headphones. Wearing headphones shows the people around you that you are not interested in talking, and that you're really interested in your music, podcast, or whatever.  Read a book. Generally, even annoying people will not interrupt you when you are reading. If they do, just reply, "I'm reading something for work/school/ that's important." A buffer can be a person who knows how to handle the annoying relatives, like a mom, dad, sibling or friend, who can deal so that you don't have to.  Social buffers should be made aware of their role ahead of time. Don't just bring one and expect them to do all the work while you hide out.  Social buffering should be reciprocated!

TL;DR in Indonesian:
Hindarilah bertemu dengan saudara yang menyebalkan. Abaikanlah saudara yang menyebalkan. Lakukanlah sesuatu seorang diri. Carilah seseorang yang bisa menjadi perantara.