So I met this new girl...

...Lisa Ann, to get my mind off Mrs. Stephanie and to relieve loneliness, which has been excruciating, online, on FB, started chatting on Messenger.  We exchanged more pics, she said she finds me very handsome, and I find her absolutely gorgeous, long black hair, smooth brown skin, likes to work out, a body to die for.  Assuming she's been honest about everything and the pics she posted are indeed of herself and are recent, she seems like a really sweet girl with a huge heart, an intelligent girl, a professional girl, successful in business, travelling the world for her company, a charity nonprofit.  She's also proven to be very needy, demanding constant attention and sweet talk.  We exchanged our sob stories about losing family members in death and have achieved a deep kinship.  We've said "I love you" many times, despite my best efforts to try to get to know her on a more intellectual level first.  She wants a husband and kids like RIGHT NOW.  Now she's deeply depressed, in pain, getting hurt and upset if I don't respond to her messages right away.  I know I'm going to have to end this.  The question is when and how to do it in a nice way without completely destroying this dear sweet needy creature.