Everybody is an illegitimate child in somebody else family. That may sounds too virtually but if you think deeper about it. It does makes sense. 

 You don't want to get involve in the other family affairs. You probably don't want somebody else parents complain and life-teaching you till your ears bleed. You may give your half part to a strange family, a half other part of you belongs to somewhere better, maybe it's your own family, maybe it's your desired/ wanted family, maybe it's your own little self freedom.  

 You is loved, but not as loved as the legitimate one. You feel like you're the favorite not until the legitimate came. You feel grateful but also jealous by the real and effortless things that the legitimate have. You feel jealous, but not so, it's been mixed with anger, miserable, hateful and deep inside pains. You feel numb and meaningless in the whole warm family. You're one of them but not really, you think to yourself it's better this way but maybe not. 

You're adjustable but vulnerable. You're loveable and susceptible at the same time, one cannot explain the exact way that you feel. Some may ask: "Is it feel like when you're being used and you gonna immovable afterward?.", "Kind of." Other ask: " Is it as the same as you want to swallow something down but can't, it's stuck and that's what make you feel uncomfortable?". "Sort of". But no one every get to understand and remember it deeply as you are. 

 Pretend to be one is never a good choice, just accept it slowly as if you reconcile someone. That's the best advice I would give to those who have been suffered and let's me give you a hug. 

Sincerely,