I agree it's too early, and this it's sad tbh that she's foisted off upstairs and told to be quiet for a whole hour just so you can eat in peace and watch the bloody tele
Really.
I also like my time to myself, and am a stickler for bed time, but at 8 that's far too early. Also think 5 far too early for tea.
My suggestion is (what works for us, my ds is almost 8) snack at 4 then homework. Then they play (outside normally) . Tea is usually 6.30 - 7.30 (absolute latest) we try to eat all together, so later to fit in with daddy coming in, or we'll eat earlier then when daddy gets in the boys sit down and eat dessert - yoghurt or fruit or something - while he has his meal. It's really important we all sit at table for meals together.
Then at 8 they go up, ablute then sometimes we'll play a game like uno or something with them, or they'll have half an hour in bed to read. Lights out 9.
We just changed it to this - before they were going up at 7.30, bed at 8, but we had more and more disturbance, kids talking, getting out of bed. I was reluctant to make bed time later as even with 8pm bed time, difficult to get up in morning, but they've coped fine, but more importantly, it instantly solved the noise at bed time.
I'm sorry, but you're going to have to accept she^s older now and you are going to loose those quiet evenings. Is she going to be sent to bed at 7.30 when she's 10? or 14? I'm sure you see that's not going to work. At some point you're going ot have to do it. Sounds like now's the time.