I am married since 26years.i am epileptic.my husband is very loving and caring. he is late sleeper.i used to s?

I Could not keep awake for him.in initial years we had sex.but later he started masturbating daily.I Took it easy.now when i have learnt that it was my mistake,i should have taken interest in sex,i am trying to have sex but he gets angry,says now we have become old.but lately i have heard of an extra marital affair of a much older person and i am really scared.i feel he is having someother sex partner.is it normal for a man of 52years to lose interest in sex.tho at times he is not angry but keeps his eyes closed and is dry.i feel satisfied that at least he was a receiver.is his behaviour normal.i think i shoud be patient.i am 12 kgs overweight even he is obese,he dislikes me wearing sexy lingeries.all this depresses me.i am trying to slim down.iwant him to be sexy.he should crave for me as i am craving for him.can you help me.