Is it 2 soon 2 love again?

A very good friend of mine husband left he for another women 2 years ago,after 18 years of marriage. she has now met another man online after many tears and low days.She has seen him about 6 times. Lat week they went away together for 4 days and i had her children. He came back with her and is now staying with her for 3 days. Her children have met him and 2 my knowledge seem fine about it. Met my friend for coffee today,asked how it was going and she said good a few arguments but on the whole very good. she says she is in love with him. Would you say it is normal after aprox 10 dates to fall in love and start the arguments already. She was so lonley i am worried she has just jumped in feet first. I have met him and i think he is ok but seems a little hard and straight talking,but i dont have 2 live with him. Any ideas just been thinking abaout it x