A new relationship with built in kids.. HELP!

"Dear Housewife,

You seem very nice, so please forgive me for this long ass message!! :-)

A little about my b/f and I: My boyfriend is 44 and has 4 young kids; 5, 7, 8, and 15. The 3 youngest are from his previous marriage. (He left that marriage to be with me) I am 23 with no kids (don't plan on having any anytime soon).

1) When the divorce was finalized, The X got awarded the section 8 and my b/f got a good amount of custody with the kids. He gets them M-F from 7am-8pm, with either Tues or Weds off. He also gets them 3 weekends out of 4 a month. Well, since he lost the section 8 house, he had no where to go, so I let him stay with me. He would have his kids on a few of the days on his turn, just because it was too far for the X to drive (30 minutes 1 way). When we did have them, I noticed a lot of flaws, I guess, with the kids: they were rude, never said please or thank you, Dad (my b/f) lets them snack all day, and didn't pick up after themselves. They always feel entitled to something they want. I let my b/f know about it and how it was a problem for me, and he always thinks I'm being critical. He replies that "They are just kids!" I don't find that to be an excuse at all. Am I being critical? Am I too harsh? Should I put my 2 cents in?

2) I have a problem with him talking to the X about what my b/f is doing. He'll tell her about our life and his, he'll ask for her advice and he doesn't even take mine. Just a month ago, he couldn't stand her, now he is telling her our life. He said she's compassionate. That really troubled me because I'm trying to be his everything and he has to run to the X for compassion! It seems every good thing about me comes with 3 bad things. Should I be offended? I feel a bit uncomfortable with him talking to her like this. Am I justified in my feelings?

3) My b/f offered the kids to stay the weekend of the 4th, and he didn't discuss it with me. They came over Sunday night and didn't leave until Tues before work. I was pissed because he didn't discuss it with me (since he is in my apt and its our vacation weekend). I was expecting to relax on our paid vacation weekend. He did it again the following Thurs! I had already asked him to discuss it with me the first time he did it. Am I not being a REAL woman for my b/f since I don't want to take on the responsibility of his kids? Our parenting techniques are so different and I didn't feel like fighting about it or being really uncomfortable since I can't tell his kids what to do.

4) Last, my b/f blamed me for the kids not being able to come over the weekend after the 4th because I wanted a break. His X just finished bitching him out for not being able to take his kids on his turn, because I wanted a break. After he finished having a yelling match with his X, I went to go tend to him, seeing if he's okay and he says "It's your fault! It's your fault that my kids aren't able to come over because you don't want to be bothered!" I told him not to make me out as the bad guy. Am I? Is it my fault?

HELP!!! PLEASE!!!"