It is sometimes hard just to snap back to your old self. It can also be really depressing when anxiety comes rushing into your life all of a sudden. That happened to me one day three years ago, and I went downhill from there because I did not realize what was going on; I thought I was going to die of a heart attack and did not trust my doctors. A good way for me to handle this, was to learn why I was thinking the way I was. I went to talk to a great therapist, went on medication, and had a great support group (like this forum). You are not going crazy and you can and will get through this. I was panic and anxiety free for almost three years and I felt BETTER than my old self. Although it has returned this year, I am better prepared to confront these issues now. This has and is one of the largest challanges of my life, but even though I hate going through it, it has made me a more patient, caring, and understanding person.
What types of things do you dwell on when you are alone? Are you still grieving over the loss of your mother?
It sounds like it could be anxiety with mild depression since you have had 2 major life events... your moms passing and the empty nest. Loss can be very difficult to deal with. Have you thought about talking to a therapist? Also you could check with your doc and see if can give you something different than ativan that you might tolerate better.
Let me assure you.. you aren't losing your mind, if that were the case than that would mean all of us in this forum have lost ours because most of us have been where you are. :-)
Jerz