I can’t have sex with my boyfriend & I’m scared he’ll cheat

I’m pregnant & got put on pelvic rest for the next month cause of placenta previa. My boyfriend & I have sex every day like without fail but my doctor strictly prohibited sex due to the risk of me bleeding even though I’ve had no spotting or anything. Anyways I’m just really scared & stressed that he’ll go out & get it somewhere else cause he’s cheated before when he said I was working too much. I haven’t told him what the doctor said yet because of my fear of him getting distant once he knows we can’t do it.