1996 Nissan Maxima no start battery fine

The other day I gave a friend a jump, my car was fine drove away no problem. The next day had some trouble starting but it started drove to my friends house. Tried to start it a few hours later and got nothing no dash lights nothing. I had my friend give me a jump car started and on my way home every time I hit the brakes the head lights would dim. The next day tried to start car and nothing, the dash lights are dim and flickering and I can hear relays under the dash and in the glove box area clicking like crazy in the key on engine off position but sometimes when I take the key out and put it back in the dash lights are bright and solid and the radio comes on but when I try to start it I get nothing and all lights and radio die they even die when I just turn on the head lights without even trying to start it. Tested the battery and its fine, I cleaned the connections and still nothing, doubt its my alternator car would still start if battery is good, doubt its my starter that has nothing to do with my dash lights. Can someone please help