Baby mama drama

So me and husband have been married for 7 1/2 months and his ex girlfriend (mom to his 2 kids) is dead set on getting between us. I hate that there is people out there ok with trying to ruin a MARRIAGE it's one thing if it's just a relationship but the fact we take our vows seriously it pisses me off. I'm also pregnant and dealing with her bull crap really affects me and it's gotten to the point after answering questions with my insurance company with their maternity part they recommend me talking to a therapist since I'm showing signs of depression and anxiety 😞 why can't ex's stay where they belong?