There is nothing sexy about trashing someone you claim to love; quickly pointing out their faults but never singing their praises. Through good and bad times respect for your partner should never falter. Proudly hold them in the highest regard. If you continue to break your partner down, someone more deserving will pick up the pieces.
The entire object of true friendship/relationships is to make people not merely do or say the right thing, but to enjoy saying and doing the right things; not merely to like, but to enjoy being admired, and not merely to love, but to love unconditionally and all their flaws.