My friend is on lovers lane...

I have a friend (she is 33)that recently got out of a 5 year relationship with a guy who cheated on her numerous times (one resulted with a child) and she had also kept in touch with with an ex who had been married the whole time they have known each other. She met this guy (this guy is going thru a divorce),2 weeks ago and already talking about marriage and selling her house within 6 months to buy a house with this guy. She feels as if all her friends are married and having children and want the same. She is very smart and accomplished but as a friend I don't know how to tell he to slow down.