How to deal with a girl who clearly likes your boyfriend?

[M]

I've been with my boyfriend for 7 months, and things have been wonderful. We both go to the same university, are 22 years old, and serious about our relationship. One of my bf's closest female friends is also a former love interest, but things didn't workout between them due to religious differences. My bf still talks to her - and I have expressed discomfort in regards to this. Since then, he always asks me if I'm fine with them hanging out together, he's given me the privilege to check his phone/Facebook IF I feel the need to do so (But I havn't taken that up, I'm not the snooping type).

So given that, I think my boyfriend is relatively trustworthy. What bugs me however is how she behaves around him. It's clear she still likes him because ever since she found out about our relationship she has been behaving weirdly around him. She's constantly commenting on his Facebook page & pictures as well - which annoys me and causes me to get moody with my boyfriend. How do I deal with a situation like this?

[Laura]

He should have already stepped in and told her that he doesnt appreciate how she has changed, and that it comes across as if she is only doing it to get at you. Talk to him about this, and get him to speak to her. If he refuses to, then he obviously doesnt care, because your feelings are more important than hers - at least, they should be.

[Nikolai Jehrkov]

Nothing a Remington 700 bolt-action sniper rifle can't fix.