Dealing with difficult aging woman. Any advice?

I met Debbie about 6 months ago. She was being abused by a childhood friend who was living in her home and stealing from her.
She is only 62 but you couldn't tell by looking at her or her mobility issues.
My husband and I took a liking to her and would visit and bring food occasionally so when she asked us to move in to look out for her we quickly agreed unaware of what we were getting ourselves into.
We're a young newly wed couple. I'm 25 he's 33. We are also expecting our first child (I'm about to pop in 3 weeks) and we felt it would be "easy" to just add Debbie to the list of responsibilities and save some money along the way.
Upon moving in we realized this was NOT the case at all. We gave up our privacy and freedom as we quickly fell into this role of 24 hr caregiving.
I mean it never ended! To the point the lady would knock on our door at 3am for simple necessities that could've obviously waited for better timing. Multiple trips to the store with a list of 3 to 4 things that had SUCH URGENCY! Cleaning after 2 big dogs which weren't ours not to mention the cleaning of fecies and urine on a daily basis.
The sad part is Debbie isn't that old but her health is declining in ways that it shouldn't be at 62. She has no children and most of her family is deceased. We've tried to help in all ways possible from buying her crafts, clothes that fit, making sure she has all her meds and food she likes all to go unappreciated and swept under the rug when a new idea hits her brain.
After living with her for 6 months now we discovered she has a horrible drinking problem coupled with substance abuse.
The woman get a nice SS check each month for it to be gone in a week and then she depends on us financially for her alcohol and household needs.
It's starting to put a strain on our relationship as we have no private time anymore plus we debate over how to fix the problems with her. He wants to just shut her up and keep her in her room by giving her what she wants and I prefer to try to do healthy things like limiting her alcohol and setting boundaries and creating a schedule for her.
The problem is she has friends who stop by who will give her illegal drugs and who knows what else and she then gets so inebriated I end up having to pick her up off the floor or clean the house as she will have accidents and not even realize it or laugh about it. (I'm 9 months pregnant mind you)
I cook, I clean, take care of her dogs, manage her bills, take her to the dr, pick her meds, and entertain as much as I can but lately due to the pregnancy I've been in pain and trying to take care of myself only to be snapped at for what I don't do.
I'm starting to feel taken advantage of and unappreciated. I'm having feelings of anger and spite towards her as she isn't even my family or related to me and I do more for her than my own grandmother (whose 70 yrs old and is starting to decline as well) although she does live states away.
I have this burning agitation and frustration with her and I can't figure out if its the substance abuse or if she really is losing her mind. I've recently just stopped. I go to the store on a certain day and ignore her to a T.
Where my husband works long days doing house restoration I'm home a lot stuck with her and its making me have crazy thoughts or anger but also I feel bad. It's a sad situation and now upon us saving enough to move since we are expecting a baby I worry as she doesn't have anyone else.
I've been robbed of my nesting time and just enjoying being pregnant and getting everything in order as she's so demanding and rude and slick at the mouth.
I've also been robbed of this last little time with my husband before we have a child to take care of (this is our first child) and the romance is gone.
I don't know what to do anymore as everything this woman does is a health hazard and I worry about mine and babies health as the incontinence is outta control and she smokes in house.
Any kind advice for young new caregiver?