Should I trust him?

I have been thinking about what I am to do about Bingley. He has all the sudden shown himself back into my life and my prior feelings are beginning to resurface. I do not want to fall back on love with him if he is just going to leave me again heart broken. But I feel as if he is staying for good this time for he acts like it. He even sat right next to me at the dinner table tonight, paying a great deal of attention to me. Elizabeth is warning me not to get emotionally attached again... but what's the harm?