As-salamu alaykum - My grandmother is making our home tense, any advice?

As-salamu alaykum. I feel awkward even writing this, but I’m struggling and could use some guidance. My grandmother lives with us and feels like a stranger in our house. She basically sits in the living room most of the day and stares at people who walk by, which makes everyone uneasy. My siblings and I have tried to talk to her or learn about her life, but she gives short, vague answers. The only real connection she has with us is biological - I’ve never felt loved or that she noticed the care I had for her. On top of that, she constantly competes for my father’s attention, especially with my mother. As soon as he comes home from work she’s at the door, chatting his ear off and asking a million questions. During dinner she’ll interrupt long conversations and change the subject entirely. If we want to watch a movie or play a game together, we often have to bend to her wishes. The general feeling is that she’s always present and it makes family time stressful and unpleasant. I feel so bad for my mother - whenever she wants time alone with her husband, my grandmother seems to take over and wants to spend every moment with him. As a Muslim I hate feeling like I’m complaining about my elders, because we must honor and care for them. I also know that respect for the husband–wife relationship is important, and there’s normally some separation of influence between a mother and a wife. One idea we’ve considered is asking my grandmother to move back to her home overseas, where she might have a more fulfilling life in a walkable community that suits her better. But whenever we bring it up she quickly dismisses it and the idea goes nowhere. Their marriage is suffering and I can’t enjoy being at home. I don’t want to be disrespectful to my grandmother, and I want to fulfill my duties, but I also don’t want my parents’ relationship to fall apart. What can I do to help improve this situation while staying respectful to Islamic values?