can or cant accept my kids?

I've been dating this guy for just 3 months. he just got out of an 8 year relationship maybe 4 months before we met the girl he was with cheated and left the state with their kid so he hardly sees his son. i have 2 kids, he has 1. all boys. he is constantly telling me my kids are bad because my 3 year old screams and throws fits... basically over everything. but it isnt as often as it seems at least once a day. sometimes one in every 3 days. he complained to his roommates and one of his roommates told me because he said it might break us up. he cant handle it. although his son who is 4 is literally spoiled and basically does the same thing my son does. my 7 year old is a little difficult to handle i admit but usually only when he is tired. other than that i believe all of them are just kids. ive talked to the boyfriend about this situation and he keeps saying he wants it to change and he cant handle a messy kid that doesnt listen. mind you i have been raising them alone for a really long time. so i find that a little offensive when he calls them bad. i dont know what to do i want a future with this guy but i feel like he doesnt like my kids... and advice?