What help an erection?

First and foremost: you've got to be together with a girl you find attractive. Never date a girl you really don't like!You've got to CHOOSE your lady but not to TAKE her in order not to be alone. When you loose interest, speak and break up. It's better making an end with tears than tears with no ending. Kids must under all circumstances be reared by both parents, but better breaking up then letting kids experience daddy betrays mom or mom is unlucky hanging on dad.
Stop talking of "inner virtues". There is the WHOLE appearance of a lady which makes her attractive to you. A screw-around mind is OK as long as you can take it - finally it's not satisfying and you will stop after finding your soul remains empty. Don't screw with ugly, stinky or dumb ladies according your taste. A soft noodle once in a while is not a catastrophic world crash. But choose only the lady you're attracted to and make an end when you secretly feel your love and erection have gone.
Finally: a little pill may help under some circumstances. It's not a remaining solution. It gives you the illusion of a mighty myth: there are pills for all situations in life. A soft noodle is mostly a head case. Try. Have courage. Smell her. Taste her. You like it? Then stay. Care. Let go. Wait and choose not a sparrow when you can go for a dove. And try not to force any thing...