Complaint Review: AARP MEDICARE COMPLETE United Healthcare

I am on disability and chose Secure Horizons Oxford as my HMO for medicare coverage.  Then They added AARP medicare Complete to name; then UNITED HEALTHCARE got invovled.  Ever since I  have had very minimal health coverage and medicine costs me e.g. $88 for one generic bottle a month.  Very upset about non coverage of my psychiatrist in mid counseling after 5 yrs having coverage ; medicine costs escalated from $3.30 for generic to nearly $90/bottle and lots of doctors and services not covered any more...Got involved in a change to straight United Healthcare and as a result denied du;e to kidney problems and chronic other conditions; and was without coverage for 2 wks! before AARP Medicate Complete accepted my returning membership.  I'm suffering badly due to lack of medical care and outrageous medicine prices.