Advice.1. Recognize when you are being a jealous weirdo. A lot of the time when you feel jealous, you'll start little arguments or say passive-aggressive things rather than talking about what's actually bothering you. (For me, it's responding to everything he says with, "Yeah, you would do that." I don't know why.) If you can acknowledge, "Oh, I'm really jealous right now because you were talking to a girl at the bar last night and it made me feel weird," that's an important first step.
2. Try to look at your relationship from the perspective of one of your friends. If you were your friend and you heard about your situation, how would you react to it? Would you be freaked out by it, or would you think it sounded totally normal and probably fine? Putting some distance between you and your relationship always helps you to see it more clearly and will potentially stop you from having a panic attack inside an H&M for no reason.
3. Focus on how great your relationship actually is. So you saw what looked like your boyfriend flirting with one of his female friends. OK. But keep in mind, you guys have an entire history between you two and a pretty unmatched closeness. Everyone flirts, sometimes without even really being conscious of it. It doesn't always mean they want to act on it. I think I flirted with the guy at my deli the other day and I could not tell you why. I think I was just tired and out of it. I really need to get more sleep, you guys.
4. Just because you're jealous doesn't mean anything is actually going to happen. I can't even count how many times I've been so afraid of something that might happen that it already seemed like it had happened and I was already mourning the loss. And most of those times, that thing I was so scared of never even came close to happening. So just because you have a hunch your boyfriend might be into someone else, that doesn't mean they're already sleeping together and he's already bought her a ring and will be proposing this weekend and dumping you immediately after inside a Taco Bell. If you have no proof of this, don't sweat it until you do. And if you're really worried about it, talk to him about it directly. He'll either put you at ease or be kind of weird about it, but either way, you can stop wondering and move on.
5. Figure out if there's any underlying reason why you're jealous. Sometimes, when we're having feeling of jealousy toward our partner, it's actually just because we're pissed at them for something else entirely. Maybe they forgot your birthday or they haven't been that supportive of you lately, and instead of just talking to them about it, it's easier to suddenly become suspicious of everything they're doing. Granted, that might not be totally conscious, but it happens.
6. Accept that you're jealous and don't immediately react to it. Just because you have a feeling doesn't mean you have to act on it. If you're feeling angry, it doesn't mean you need to throw stuff or yell at the nearest person in your coffee shop. You can just realize, "Oh, I'm feeling angry right now," and see if it passes. Same goes for jealousy.
7. Let go of any old relationship garbage that has nothing to do with your guy. Maybe you're worried about him cheating because your ex-boyfriend cheated on you or your dad cheated on your mom, but that situation isn't the same one you're in now (hopefully). Your current partner has no ties to anything that came before, so putting them in the same league as people who hurt you or the people you loved in the past isn't fair to either of you. There's a reason why your old relationships didn't last and this one did.
8. Believe with all your cute little heart that you deserve to have someone love you. A lot of the time when we're jealous, it's because some part of us believes that we're unlovable and that our partner could do better, so obviously they would and will. But it just isn't true. You, right now, with all your flaws and shortcomings and struggles, are super, crazy lovable and worthy of having a committed partner, which is why you currently have one! Don't let some pointless belief that you're not as good as the hot girl he talked to at lunch mess with your head. 'Cause honestly, she might be gay anyway. You never know