What is the best temperature to keep the house during the summer?

So my family and I are having a bit of a trouble finding some compromise. If it is too warm when I try to sleep, I either can’t sleep or get physically sick (I wake up with extreme nausea if it is 75F in the house). It’s just too uncomfortable and I can’t get any proper rest. Because of this, I like it at 70F. My family (60+) likes it at around 74/75F and have not been turning the air conditioning on. Lately, it’s been getting to 80F outside, so I can only imagine what it’ll be like come June. It’s hard finding compromise because even with my room fan on and door open, it’s still too hot for me. The fan doesn’t make the room cooler and it’s just annoying having all that air blowing hard on me when I’m trying to sleep. What should we do? It’s starting to get very troublesome waking up in the middle of the night sweating and feeling sick and having to turn the heat down…..especially since I’m the one in the house that has to leave the earliest….I really need my sleep…