My son won't have his own room after all.... Long story 😥

So my husband and I have been decorating our baby boys room. We painted it, put up his name and stickers. We had his clothes hanged up and folded. We excited! Well All that changed in an instant. Yesterday my niece and her husband who have been staying with us for maybe a week now, broke up. My niece is crying, idk what to do. I only have two rooms and she has a baby boy herself. So what am I to do? I can't throw her out she's my niece. So I offered her my sons room not even thinking about it. She said no that her husband will come back or she will go back. I told her he might not let her in think of your son. She cried and came to realize it was true.

It hit me this morning that my son will no longer have his own room. I feel like I'm being selfish and hubby isn't happy about it but he knows we can't throw her out. So we basically waisted paint and time decorating the room for our son. I'm sad and selfish and I won't resent her because it's not her fault. Now I have to figure out how to fit the baby in our room :( I'm sorry just needed to vent. Thank for hearing me out.