I would suggest becoming more comfortable with letting your feelings out (in an appropriate private location) so that when you experience the losses of life, which come to us all, you can stay in the present moment and truly feel your feelings -- without being afraid of them. It is the fear of the feelings that may be what brings on DP for you.
To become more comfortable with experiencing your feelings, you could find a qualified therapist or you could experiment privately with allowing some of your sadness to be expressed in a situation where you are the only person present.
Many times recently I have found that when I try and try and try to play something on the piano, and then I finally succeed, or if I am trying to create a nice melody or find a chord or something and I actually manage to do it, I just start crying. Those are tears of something or other -- joy, maybe? But it feels so good to let whatever it is out.
The same is true of when I think of my poor mother, who's lost to me but physically alive (Alzheimer's). She's not suffering, but her loved ones are, and sometimes the feelings just well up in me and I cry like a baby. It hurts so much, so terribly, and I used to avoid the tears because I didn't "want to wallow in feeling bad." But that's not at all what happens.
We know intellectually that we are going to lose every human being we know, provided that we don't die before they do. So, intellectually we accept the fact that death comes to all. But coming to terms with it means recognizing the way we are wired to FEEL about it. We hate it. It scares us; and our feelings about it scare us, too. But I have learned that avoiding the feelings is what causes psychic malfunctions. We are wired to cry and weep, to laugh and grin, to love and cherish. All of these are wired into our bodies because when they all work properly, they bring us health of mind and body.
So, back to the beginning: Find a way to become comfortable with feeling your feelings. It is most often an eye-opener to experience this life-changing thing in the presence of a professional who has lots of experience with helping people accept and express their feelings.