No sex in our marriage

Ji

Okay so I need to know on average how many times do you guys have sex in a month? I’m low on sex drive, but during my ovulation days I do get horny. It’s been almost 5 months we haven’t had sex. This year we had sex once in February & second time in June. Husband & I have been married for 12 years. I’m 32 he is 36. Am I overthinking if I feel he has an affair or doesn’t love me anymore. Also in our 12 years of marriage I have never initiated first. I don’t know why but I can’t. I have seen him masturbate many times in the shower. I feel bad. Please help! Tell me what should I do?