husband talking bad about me to kids?

yet he talks good about his ex wife to them. i feel so disrespected. he does this behind my back, but my son told me about it. he said all daddy ever talk about is his ex wife, he always say good things about her. but when it comes to him talking about mommy, its all bad. i feel like he still loves her, if he had the chance to get back w her, and divorce me, he definetly would! my husband said all we ever had were problems. i understand that shes a part of his history cause theyve been together for 8yrs, were middle to high school sweethearts. but still, its very disrespectful, its like hes trying to turn them against me.