About to have a breakdown .

So I have two stepdaughters 4yo & 5yo, their mother gets them every other weekend. Im ripping my hair out because we have been dealing with this for TOO long, every time we got them back from their mom they have lice and are in poor condition, they brought bed bugs over to our place about 7 months ago. We have been battling lice and bed bugs for far too long and I’m so upset they’re so hard to get rid of. 😢 I feel like we keep spending all this money on bed bug and lice treatments, but it’s just not going away! (We get the lice out within about a week or two) then their mom comes over wanting to get them but my husband refuses because of the poor conditions they are in when we get them back, he tries to explain why he doesn’t want them to go with her for the weekend she tries to flip it around on US! When we are the only ones trying to make the best life possible for them. We’re stable, she’s homeless she stays at her moms then her brothers and back and fourth, so when we go get the girls from her, she’s nowhere to be found! My husband goes to court next month to petition for custody, so wish us luck. But I really need tips and advice on our bed bug situation. It’s driving me insane I feel like I have tried everything, literally about to break down. 🥺