Suggest Medication For Depression And Anxiety

I have been diagnosed with depression in 1999. I have noticed average improvement on 40 mg citalopram, but still felt moody in the evenings. I used to be depressed for 2-3 weeks continuously and used to feel better f0r 2-3 weeks. My doctor added lithium 450 mg. I did 0 not notice any improvement for 1 yr. Then he increased citalopram to 80 mg. My depression was cured completely in 2 months time. I never took citalopram 80 mg contnuously for more than 2 months. I used to decrease the dose to 40 mg once I felt i am doing good. Within 3 weeks after being on 40 mg, I used to get mild depression symptoms. Then I used to increase the dose to 80 mg. I used have mild depression symptoms for couple of hours a day for a week and other week totally fine and again experienced mild depression a couple of hrs a day. This happens for a total of one month when i get back on 80 mg. And again i used to cut back the dose to 40 mg. From 2010 jan i took 80 mg citalopram continuously for 8 months. It suddenly stopped working. I tool effexor 300 mg (increasing from 37.5 mg). After 3 months, I felt a little bit improvement in depression, but terrible increase in anxiety and crazy thoughts like why people live, why people do what they do and fear of killing myself etc. I used to experience these anxiety thoughts every alternate week. I have stopped taking effexor. Started taking lexapro (40mg) since 1 month. I am again experiencing a similar thoughts ( thoughts experienced during on effexor) since 3 days . is this common to experience those for a while even after I stopped effexore.