I'm so pissed

So we go pick up my step daughters and we had to go to their mothers house which isn't suppose to happen we have a mid way point of meeting. Well I had my son so my husband went in to get them. FORTY MINUTES later he came out, she said they were asleep, she had to change them and put clothes on them. She came out of the house in a see through shirt! I flat out told my husband he ain't ever going back into her house even with her parents home, and next time she decides to be inappropriate with him (she'll always tell him how she misses him or how she wishes things were different and everything ) the hormonal pregnant lady ain't gonna be holding her tongue anymore. Cause I swear she just tries to push all my buttons too see how far she can push me till I snap