should i delete my exes nudes if i have no proof he deleted mine?

Yes .. it's me again.

Delete the photos and get on with your life !

Can I also give you some advice.
If you are not happy in a relationship then you aren't with the right person.
Yes .. there will be "ups and downs" in any relationship, but the basics like "trust" and "monogamy" are essential.
Looking back through previous questions it is worrying that there have been times when you have wished that you hadn't been born and you've been "silly" with paracetamol .. there is also a suggestion that you may be bipolar !
You need someone in your life who cherishes you .. not someone who you don't trust .. and I hope you meet him one day.