Is my boyfriend cheating???

So I’m 23 weeks pregnant. So before I got pregnant my boyfriend couldn’t keep his hands off me. We had sex every day sometimes multiple times a day. Well now that I’m pregnant everything has changed. I’m lucky if we have sex 2 times a week. He always claims he’s too tired. He don’t kiss me anymore besides on my forehead. He started ignoring my texts. He used to send me I love you texts through out the day if he’s at work or if I’m at work. Not anymore. Idk what to do. I asked him if he’s not attracted to me anymore he said he still is. I’ve told him multiple times that I would like to have sex everyday and he says he won’t mind. But it never happens. Even if I try to start something he just turns away and goes to sleep. Can someone give me some advice? I’m really starting to think he’s cheating?