Hi Ginette
I can really understand how you feel - at first when they leave it is such a huge life change for you, so no wonder you are feeling down. I too am lonely, it has happened over the last few years. I lost my parents, and others of that generation, so feel rather lost as the family has really diminished.
Now when I compare my life to friends, they have young granchidren living locally who are a great joy and interest, plus their own children, always things going on in their livs. One of my children is living in other side of the world, the other is about 200 miles away, so I rarely see them, and like you have no grandchildren.
I just have to accept that this is just the reality of my life now, and try and get on with it as happily as I can (easier said than done). I don't want to get anti depressants, because I feel thats not a good move.
I too really need to make some new contacts locally, as Elegran suggests to you. Personally I am going to try the WI, as it is quite a young group with a walking club attached, and hope they are friendly.
I find that if I do have an unexpected meetup and chat with someone, it really lifts my spirits. Hope you can get something new in your life too.