Why are people liek that?

They say 'I miss you' but then don't text me for three days. Say 'l love you' but don't care when I'm excited or have a mental breakdown. Get mad at me I distance myself after they be unfair, disrespectful and I tried to communicate but it didn't work. So I stop text first and then they are mad that I am closed off? 'but I have bpd!' yes and I'm also chronic mental ill, and I don't use it as a excuse. You can't bully or do shit liek cheat and then act like it's okey because you have bpd. Say 'sorry' but you do it again, say 'you're important' but I don't see or feel any of it. If you do shit what could be abusive or criminal it's all fine but if I don't text because I was on my grandpa's birthday even I said before I can't then I be avoided and distant? Come on, that's just bullshit