Why did Summer invite him to the party?

She probably wanted closure in some form, or maybe just wanted to see if he was okay. She clearly cared about him but didn't always go about showing it in the right way.

I think she genuinely likes Tom as a friend. But she's so self-centered, she doesn't understand that he would get hurt when he sees her engagement ring.

It wasn't so much her inviting him to the party that bothered me but rather the fact she didn't all prepare him. They spend virtually an entire weekend together and not once does she mention she has a serious boyfriend - not even when she invites Tom to a party that she knows her boyfriend will attend. So much of the film rings so true - frighteningly true at times - but this part does not. I simply don't believe Summer would be that heartless.

because she's a *beep* self centered bitch that's why

very real with how most women are these days

hard to watch but an important film indeed; debunks the whole women are innocent argument

That was hard for me to watch as well. Up until that point I wasn't that sympathetic with Tom because Summer had been upfront with him.

But then she acts all flirty at the wedding and invites him to the party...again, I didn't necessarily think she was interested in rekindling anything, but thought she still had feelings for him. But when we see her showing off her engagement ring, I felt so badly for Tom. And she also throws in the dig "Tom wanted to be an architect." The whole thing is very cruel.

On another thread someone mentioned that she keeps popping up and holds his hand at the end to maintain her power over him and I agree with that analysis. I think in her mind, she thinks she's doing the right thing, making sure he's OK, etc. But really, she just enjoys knowing that anytime she wants she pop up and he'll look at her all googly eyed.

Girls, eh!

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uh, what do I know ?!?

I feel it was more or less her reaching out to him as a friend. She throughout the movie made it very clear she valued him but just as a friend. His unrealistic expectations are what makes Summer seem so cruel, whereas she was just hoping to casually reintroduce him into her life by inviting her to a party she was already having may I add. This party wasn't for him. Summer did what any person would do after bumping into an old friend knowing you have a party coming up. Sure she lead him on a bit but that's just Summer. Finally to all the people talking about how awful women are and how difficult this movie is to watch don't understand the message of the movie and really just need to get over themselves.