This is a stage that hit me and every bf mum i know at exactly 5ths. i was at my wits end too. my lo is 7.5mths now and it is slightly better. they are becoming my intereted in their environment, touching, looking, sounds and much more engaging. the things i do to get through a feed:
1. sit them up to feed, sometimes try facing the toward you straddled.
2. feed as long as possible, put them down to play and feed again at intervals. get down on the floor with them in your lap to feed.
3. the quiet room didnt really work for me becasue there was still something she wanted to touch etc, i have found lying on my bed with her beside me keeps her attention a little longer.
it is a very time consuming to feed at this age, you need to be extra patient and know it does pass (somewhat). If all fails or you finally run out of patience i found in the end she still lasted to the next feed and usually fed that little bit better because she was hungrier. Finally, they do become more efficient suckers so you may be surprised how much your lo actually is getting.