Hi there,
i really wouldnt let this get to you let alone ruin your reationship. Your husband evidentaly loves you a 35 yr marrige is proof of that and please do not let it destroy your self confidence. Ok so he likes to lok at pretty young things with fake hair, fake tan, fake nails and fake boobs having sex with young steroid riddled men, its purely superficial. And I very much doubt hes think of them whilst with you.
Its proven that men get turned on by "visual aids" whilst women get turned on by more mental things such as fantasising. Can you honestly say you've never had a quick daydream about david beckham or brad pitt giving you a massage. I know I have!!! And it doesnt mean I love my partner any less nor do I ever wish I wasnt making love to him.
The fact he was trying to hide it from you means he was try to protect you. He loves you and your journal probably showed him how much you were hurting which upset him greatly.
The spywear you have on your computer is a breach of trust and if he found out could ultimately wreck your marriage. Trust is the basis of a good relationship, which you obviously had. Please dont throw that all away.
My partner looks at pornography yet I know he is devoted to me and that is just something to 'relax' to. Please dont let it get to you. If u ever want to talk, im here. Good luck