i just know it that hes cheating, what to do?

but i dont have proof, however theres signs, and i feel like hes even trying to tell me he is by his actions. he dresses and fixes his hair nicely at most times whenever hes going to pick up his weed. he used to dress like this when we 1st start dating, but stop after we dated long, and no longer does after we married. sometimes hed shower 1st when he already showered. if he doesnt have time to shower, he switches undies. hes very secretive w his phone, email, and money when he wasnt before. he doesnt let me go w him to pick up weed because he says it doesnt feel right. he says it feels like hes bringing his kid along. sighh, idk what to do anymore guys... i cant leave him at all. i cant see my worth. i just feel it that hes cheating on me. hes probably so happy that im not doing anything about it and hes getting away w it. i just need evidence 1st before i do anything. but it seems impossible to get evidence.