I will attempt to keep this very long story short!

My boyfriend and I are 33 and 28. We have been together almost 8.5 years. We own a 3-Bedroom townhouse with our 2 larger dogs and currently have no kids (we are TTC).

Due to SEVERAL poor financial and life choices, my "MIL" is losing her home. We have bailed her out on more than one occasion, but we just can't do it again. We have nearly wiped out our savings helping her, only for her to put herself right back into a hole. What we have left in savings is for potential fertility or adoption expenses since we have been TTC for 7+ years with no luck (one ectopic pregnancy this past year).

She asked to move in with us when her house is foreclosed on and we have told her we don't think it would work out and that none of us would be happy with the living situation. She has been dismissive of these feelings.

She has known of the seriousness of the situation for months and has made no attempts to find other living arrangements, like putting money up for an apartment or anything. She works FT and there is no excuse for her to not be able to afford to live in a small apartment. So - Where does her money go?? To my POS sister-in-law with 4 kids, no job, nothing! She has bled my MIL dry to the point where she will lose her home! However, MIL has allowed this to happen by not enforcing any kind of "rules" or expectations on the daughter. As I said, we have spent $1,000s (maybe even $10,000+, I will likely get sick if I actually added up true dollars...) saving her home or in the past and occassionally supporting the household of now 6 (utility shut offs, diapers when we stopped by and saw the two babies running around bottomless...I'm trying to not get started on the whole SIL issue on this post)...

No one knows where SIL and 4 kids are going, but she seems to have something "in the works" so we don't ask. We just know it will NOT be with us.

But, SIL is a whole other topic, so back to MIL... She has now begun making comments like, "when can i bring some stuff by?" Or, "I'll likely have to rent a storage unit because the middle bedroom won't be big enough for everything of mine." Uhhh, what??? First, we have not agreed to this move... Second, the "middle bedroom" is our future nursery!! She has already laid claim to our nursery! She is not being humble about this potential move AT ALL.

My boyfriend and I are in agreement that she cannot live with us. However, that's easier said than done. How do you turn away your mother, or MIL, when she's standing at your door with nowhere else to go? I told my boyfriend we need to sit down with her and explain how it will just not work. He is thinking of offering to pay up to $500/mos rent somewhere for her, and any security deposit necessary. I'm not quite onboard with that idea yet, but I'm also not ready to share a home with her. I know she will lay the guilt on us heavy during this conversation. My BF will cave. I should mention he is the youngest of 4 and the other 3 siblings aren't even phased with the fact that their mother (and now sister and 4 nieces/nephews) will be homless very soon!

I guess the specific advice I'm looking for is:

1) Am I being coldhearted in not entertaining the idea of her moving in?

2) How do we turn her away?

3) Am I being selfish ramping up TTC so if it happens we can simply say "Oh, we're pregnant, there's no more room here."

I fear her moving in will delay us having a baby, will destroy whatever is left of our relationship with her, and will strain our relationship too. I just don't see this ending well at all... Thanks for taking the time to read. Any words of guidance are appreciated!!