I personally don't avoid situations that cause negative feelings just on the grounds that they cause negative feelings. That's a personal choice that I realise some people opt not to make, and that's perfectly fine. But for me, I use negative feelings as an indicator that my attitude needs to change, because usually it's not the situation itself that's the problem, but my perception of it.
The world is a yucky, scary place. If you let that stop you from doing things, you can easily live life under a rock. Some people just don't want to deal with yucky, scary things, and they skip from one situation to another, never really finding happiness because they're always looking for greener pastures.
I'm not saying you should always jump in to a negative feeling situation just because it feels negative, either. That would be dumb. Some negative feelings are a sign that the situation is harmful. But with a little practice, it's possible to distinguish between negative feelings that are warning signs and negative feelings that are opportunities for growth.
But on the specific topic of insecurities, that's almost always an opportunity for growth. I mean, obviously if you're insecure because your current partner has cheated on you repeatedly, that's a different story. But if you're prone to insecurity regardless of how your partner behaves, then it's probably a sign that you have some internal shit to deal with. It's a personal choice whether to deal with your internal shit; many people live their entire lives without doing so. But I tend to avoid those people, because they tend to blame others for their problems, since that's the story you need to tell yourself if you don't want to do the hard work of fixing your shit.
Gralson: my husband (works out of town).
Auto: my girlfriend (lives with her husband Zoffee).
The most dangerous phrase in the English language is "we've always done it this way."