What is my status if I sever ties of kinship with my in-law who is not good to me? Does this affect my fasting in Ramadan?...

Fasting is obligatory upon every sane, adult, healthy Muslim male who is not traveling at that time. As for a woman, she must not be menstruating...

The one who is fasting is happy at two times: when he breaks his fast he is happy with it, and when he meets his Lord he will be happy that he has fasted...

It is preferred for the fasting person to hasten in breaking the fast when the sun has set. Sahl ibn Sa`d reported that the Prophet said: "The people will always be with the good as long as they hasten in breaking the fast." (Related by Al-Bukhari and Muslim.)