Don't know what to do.

Hello everyone, so there's this girl I've been with for almost 6 years. I've been leaving with her for quite some time now. Whenever I am with her, everything seems good and we all happy around each other. There's a guy working abroad, whom she got introduced to by her relative last year(2017). They've been in constant communication whenever I am away. Recently, I found out that the guy was coming back to his native country in a weeks time and my lady started behaving in a suspicious manner. She would always start a querrel with me, always get mad when I missed her call, make a lot of WhatsApp calls and even got more mad when I asked her if she was talking with the guy.

At that time I was in another town, then decided to go to her place ( where we were staying together). That day she left me house keys and left hurriedly we did not even meet. Later on she came back in the evening and apologised to me saying that she was going to a friends wedding and she was getting late at that time. At night, I accessed her phone and realised that she had actually gone to meet the same guy who came from abroad. I got mad and confronted her, but she really got pissed and said to me that her phone is hers and she even refused to talk about the issue. Two days later, I was in town then surprisingly spotted her alight from a public vehicle. She did not see me, the I called her just to confirm her location. She said she was at her work place. I followed her until she met with the same same guy. I did not want to inturrupt them. Later I met with her and she denied that she had met anyone. I then treathened to live her but she cried and begged me not to love her. She then said that the guy was just a friend and nothing was going on. I had completely lost faith and trust in her, which drove me to monitor her phone. Up to now, I am staying with the Lady and she is still talking to the guy. When I confront her, she gets mad and doesn't want to talk about it.

Please advice me on what to do now since we have invested in the relationship and I do love her. I just don't want to loose her, and I am still sticking to her because she has not had any sexual contact with the dude. Am I doing the right thing?

Thanks.

No, I don't think you're doing the right thing sticking by her. I'm sorry OP, but your relationship is on its last legs.

She's been lying to you about him, and you've resorted to snooping and following her. This is not what a healthy union looks like, and you might love her, but she is showing you very clearly that the love is not exactly mutual anymore.

I think it's time for both of you to get real about where your hearts are at. Hers is drifting further and further away from you. This other guy is just a symptom of a bigger problem.

Sorry this is going on... I want you to know that I am praying for you and your relationship.

She's cheating and this is now a cat and mouse game, not a relationship. She's cheating. Believe it. End it.

we talked alot and promised never to mess up our relationship over the guy they met for only 3 months. I installed some spy app on her phone and now I know she lied to me about not messing up. She talked and texted the guy. I even noticed that they kissed and had some touching while at the guys place.