Should I trust my brother when he said he and his friend saw my gf cheating?

Both him and his friend said they saw her making out with another guy in her car (the guy was in the passenger seat) and driving away as they were heading to the gym.

The reason why I'm asking is because he wasn't quite the best brother 7 years ago, he did something bad and really hurt me. I was engaged at the time (I was then 24 and he was 19) but broke it off because I found out she cheated with him. He was remorseful afterwards, kept promising he wouldn't ever hurt me like this again but it took me about 3 years to reconnect with him. Since he's my brother and I couldn't find it in me to hate him, I forgave him but never forgot (we just don't mention the topic and haven't for the longest). As for my ex fiancee, I went permanent NC with her.

His friend is saying the exact same thing. But should I take my brother's word this time? He claims to have learned ever since, that he wants the best for me, isn't after my gf and is just informing what he and his friend saw. In addition, our relationship has been nothing but argument over these past 3-4 months and she apparently seems to be busy on some day, claiming that she's been working on double shifts.

From this information you cannot know, but you owe her the benefit of the doubt. Your brother may simply remain a very jealous and reactionary sibling. In which case all such sensitive information requires to be verified, either by you, or otherwise somebody which you can trust from your own personal experience. The first to exclude from your trust must be his friends. It may well be true, but also, it may well be not. It is not the most probable time to begin such activities, when driving away. for you are focused on the road, and shifting the stick. Having driven away, yes. If they are claiming that he made a move on her you can be fairly sure that the information is false: celebritydiscodave.co.uk

I'll confront my gf sometime later on today. From my understanding about cheaters, if they tend to get defensive it means they got something to hide. I hope it's not true but I don't know. Our relationship hasn't been too good these past months.

She is very likely to get defensive because you are actually supposed to trust her, so definitely do not draw any conclusions like that from it. Do n`t confront her, continue as normal. If there is something going on you will find out first hand eventually, but meanwhile you are absolutely obliged to trust her, she`s your girlfriend, not some stranger. Meanwhile, see if you can improve on your present relationship with her. You are prepared for the worst, and this is all that matters there. If it turns out to be true do n`t beat up on her too much, try and forgive her. Caring for somebody should not be a matter of ego, and if it is truly genuine your caring will come out on top, no matter what the circumstances. Be abundantly better than the competition even when you come second to it.