Would like others opinions on this please.
My DH (been married for a little over a year) is currently having issues with contact for his daughter due to his obstructive ex. We were discussing it with his family members when his sister made a comment 'maybe she's doing it to get back at you for cheating on her' I literally had no clue 
After a long talk, he said he had been unhappy for years, only stayed for his daughter etc & did cheat 6 times full sex (including a 4 month fling/affair, this woman wasn't aware he was with someone) & countless kissing, flirting with others etc.
This has made me feel very strange & like I can't trust him
.
Can people be different/loyal/trustworthy in other relationships?