Indifference or pride?

I just had a problem with my roommate. But, unlike the usual me, I have no urge whatsoever to mend this relationship.

I wonder if that's my age that make me too snobbish as to refuse to start a reconciliation. This time I have no guilt whatsoever. I expressed my opinion, she said it's OK, but then she acts in contrary: making the condition felt not OK at all. Yet she told me it's OK eventhough now she avoid to even talk to me, avoiding eye contact when she really really have to say something out of politeness, let alone discussing what actually she has in her mind.
And I just let her... she was the one who said it's OK anyway.

Or is it just that I'm getting more mature to know friends come and go, but good friends stay.
I think the fact that she made such a happening over my opinion proves that she doesn't worth any of my effort. I almost never express my opinion anyway, and look at what happens.

Beside it's been a long time since I notice I have many disagreement towards her definition of a friend. It isn't really matched with mine. And I can even say I despise some of her way in treating a "friend".

Provided I had behaved normally to her, on which she reacted abnormally, I don't think that I should have a problem here. She want to have an issue with me, there, she can have it. But, I don't have anything against her.

So, I guess I am making my first ever decision to abandon a friend here. I hope with this writing I can ease my mind and stop thinking about this problem: use my brain for a better use.