what can you actually do if you're scared of ending up alone

once my elderly mum and dad are no longer around i will be completely alone....i have lived alone 19 years coping with severe mental problems, my parents now live far away from me, so i feel isolated, alone and cut off sometimes....and i often worry when my parents are gone from this world i will be left completely on my own...and i honestly despair about it.

i lost touch with my friends from the past, and my only ambition has been to find a loving partner, a wife....but so far that has never happened and i'm 46 now.

is there anything i can do to avoid a terrible fate?