nightmare about falling from a roof,can anyone interpret?

Anyone able to help me with this dream, troubled by it since having it several months ago.(sorry it is lengthy but have tried to put in all factors that may have a bearing) I am on a roof in Lark Lane ( a buzzing place of bars and eating places, arty crafty shops, in Liverpool) With my daughter and we are close to the edge of the roof. My friend Joe calls to us from another roof ( he has worked in the past fixing roof in Lark Lane, this is work he has done for a long time,now in his 50s and probably shouldnt still be doing it as he has health probs though very wiry and agile still) My daughter steps forward when Joe calls, and falls from the roof. The dream then splits into two...I am feeling deep anguish and sorrow and shock as she is falling to her death and there is nothing I can do to stop...and at the same time I can hear her saying to herself, oh God no! and i feel her terror...then I wake, feeling great relief but also the sense that i now know the trauma of losing a child without actually experiencing it in real life. Our situation is that I have suffered with M.E. since 96. much improved now but far from previous level of physical health ( though a lot further on my spiritual path) My daughter is 27 and she too has had this illness (for 6 yrs.).she is improving and hoping to return to her 'normal' life soon, finishing her degree, moving into a flat with her fiance. She is an old soul, much older than me I feel ( and have been told two or three times) Bless you if you stayed with me this far, any ideas anyone please?