Adapted from a recent online discussion.

Dear Carolyn:

I'm a 20-year-old female college student. My last ex-boyfriend of five months was abusive: emotionally, mentally and even physically (a few times).

After a particularly ugly incident, I dumped him. About a week later, I got into another relationship with a wonderful man who has been my close friend for six years (we are now two months into a relationship). I love him very much.

Sometimes I still blame myself for the lying and abuse from the ex (and sudden (jerk) antics I endured from previous boyfriends), and I'm afraid of it happening to me again. How do I learn to trust my boyfriend and get over my past experiences?

-- Traumatized

You can't -- and, arguably, shouldn't -- trust this or any other boyfriend until you trust yourself.

Not that all guys are bad, obviously. It's just that getting into a healthy relationship requires more than just two decent people finding each other (i.e., people who feel obliged to be good to others for the sake of it). It also takes honesty, confidence in your ability to read your situation, and a pinch of skepticism -- not so little that you rationalize every bad thing you see into the best-case scenario, and not so much that you're chronically jealous, suspicious or fearful.

There are plenty of decent people out there, and it's possible to find one even when your sensors are on the fritz.

However: Keeping your equilibrium when you're with this person will require either a healthy outlook on your part, or a very forgiving one on your partner's. That's because people who aren't confident in their ability to read situations accurately -- i.e., people who don't trust themselves -- tend both to rationalize away serious problems, and to overreact to minor ones.

Since your confidence is shot, I suggest you concentrate on building it back up by trying to make sense of all those (jerks) and their antics. Specifically, you want to figure out what role you played in choosing and trusting men who went on to take advantage of you.

Since it's hard to have perspective on yourself and your past while you're dating someone, consider recruiting outside guidance through your college's health services.

Otherwise, you'll have to exercise the discipline to take a self-guided tour of your own frailties, by looking for patterns in: the men you seek out; the urgency of your searches; your behavior with these men; the behaviors of theirs you put up with or explain away; your emotional habits growing up; the habits you observed in your parents. Figure out when you under- and overreacted in the past, to what, and why.

Don't be afraid to bring in ideas that seem unrelated -- for example, your attitude toward school or achievement or friends or money or general conflict. These provide clues to what you care about, where you seek happiness, where you actually find it, and what trips you up along the way.

Having that emotional map to guide you within a relationship won't make you clairvoyant or invulnerable, but you can get a lot smarter about what's safe for you, what you need to be careful to avoid, what reflexive responses tend to get you into trouble, and how to recover from mistakes.

Tuesday: About those insecurities ...

Email Carolyn at tellme(at)washpost.com, follow her on Facebook at www.facebook.com/carolyn.hax or chat with her online at noon Eastern time each Friday at www.washingtonpost.com.

(c) 2012, Washington Post Writers Group