Widowers and Daughters, What a Challange

I have been dating my partner a widower for the past five years. We met and started to date five years after his wife died. He has two daughters who wewer 19 and 21 when we started to date. We had a great relationship but always with stronger feelings on my side. I know I love and would marry him in a heartbeat. He has never felt that strongly. I am very close to his elder daughter and have always bonded with her. With his younger daughter I have never been so close. She graduated from University lasst year and since then has been living at his house spending her time partying and travelling. We each have our own houses. I got dumped last Monday. The reason given was that he does not love me, and his younger daughter doess not like me and he does not have strong enough feelings for me to challange his younger daughter. This came ouat of the blue and we are now seperate. My like is destroyed and I am distraught. I cannot see a future without him. His younger daughter will be travelling overseas for six months shortly. Should I wait for then and try and get him back or will I only be hurt again? How do I cope?