My dad is 78 and has become anxious and withdrawn over the last 18 months. He is also quite demanding and needy because he has nobody to bounce off. My mum died 20 years ago and he has a lady friend who lives an hour away but since covid he's nervous about using the trains, and driving worries him so he no longer sees her.
He has never babysat or played with my kids, though he has come round in the evening to watch the house while they've been asleep, and when they were older just been downstairs as an adult on the premises. He's occasionally asked then how they're getting on at school but there's no kind of relationship. My eldest is at Uni now, and the younger one 14, but she's sullen and awkward round him, and he says to me she is rude, and ignorant because I often invite him over as I'm conscious he is lonely, and she stays in her room. He recently got a smart phone and is causing quite a few problems with it, texting random hurtful and troublemaking messages to myself and my hubby. He has nothing to do all day and is semi-reclusive, so he overthinks. I work full time, and do volunteer work 2 evenings and my hubby works away at Heathrow during the week. My son at Uni also works a 30 hour week so we are all quite busy, but Dad will text, expecting an instant response because he looks at his phone all day. I've explained that we oftdo look at our phones (son & I aren't allowed on them at work except emergencies and breaktimes). He sends messages saying how disappointed he is with us which really upsets me, but I understand he's lonely and feels isolated. However I'm a bit torn because I really have to watch my own mental health. I trained for a marathon earlier this year and he was very negative about it, saying it will kill me. And I actually dropped out of training because he convinced me I was being selfish, but then I put on a stone and he started making me feel fat because he said I have to modify my diet because I don't exercise. And I just thought I was being controlled/gaslighted so I managed to get my training back on track and did the marathon in the end. But it was almost in spite of him, because he holds me back with his negativity. But often he is complimentary and offers supportive words when I'm down. I just feel it's all part of a kind of subconscious effort to be in control because he has not much else.
I mention this just to give perspective. I'm prepared to have a chat with my son and daughter and ask them to be a bit more accommodating, given his situation But it's really tough sometimes striking a balance between supporting him with the little free time I have and trying not to take on board the unkind negative remarks.
How can I change the way I approach this so we have a better relationship with him?