Hi Donna. I also recommend that you go. Last year my brother backed out of a trip to Paris with me. I had a fantastic time. I did a lot of pre-planning at home; I didn't always keep to my planned schedule but it helped me to relax to have plans made. I did stop often for coffee or a glass of wine at cafes, outdoor when the weather allowed. I took my journal with me and caught up on it at the cafe; a 5 Euro coffee or glass of wine for an endless time to people watch, journal, check my guidebook, listen to others patrons conversations at the cafe was one of the favorite parts of my trip. One afternoon, while at my neighborhood cafe in Paris, there was a demonstration (peaceful) against the government and their handling of immigrants; it was fascinating to watch hundreds of people walk by with banners, flags, horns, drums, etc. Many of them stopped at the cafe for a drink, GREAT people watching. I took some pictures from my seat at the cafe, most didn't turn out well, just a bunch of people walking by, but the memories flood back when I look at them.
Another good part of being alone was that I could shop for as long as I wanted! I love open air markets, and I went to several on that trip alone. If you can find some food markets, I would recommend going. I didn't always buy anything, but the atmosphere was great. I spent some time clothes shopping on a rainy day; I can't imagine that my brother would have been patient with that!!!
I went to dinner early and then relaxed in my room in the later evening (I usually had a walk after dinner but my feet were probably sore from all the walking during the day). When I went to dinner early, a couple of times I ended up chatting with other English speaking patrons, that helped with any loneliness I might have felt. I also chatted with the hotel staff a bit. I found an English bookstore and bought a couple of books to read; that helped fill the evening too.
Have a great time on your trip.