>>40810613 (OP)
That's a good attitude imo, people always cheat on you when they loose interest. 3 times I had a serious relationship, 3 times it happens. Also I think it's because I usually don't want to have sex on a regular basis after 6 months of relationship.
So I think the best way to deal with that and never be disappointed, is to not engage into a serious relationship and just have polyamourous situationships