I don't know why you TLR dudes are so fukking obsessed with the thought of women cheating. How can you be so sure that his lady is cheating when yall never met her? OP you got to take the advice you getting from these scorned nikkas yelling "you share that girl" every chance they get with a grain of salt b/c they most likely still got their soul burning from a previous relationship.
You know your chick best. By now you should have a third eye about her behavior when you're not looking. If you don't trust her anymore, then end it b/c you'll most likely never fully regain that trust and that will lead to a lot of problems down the line. There is also a very good chance nothing mischievous is going on. This could be a case where your woman was talking to one of her girlfriends and heard about all the great things their boyfriends were doing and she compared it to your bum ass living life with no plan. I didn't read the whole thread but if your chick is in medical school then she is around successful, passionate, driven people all day....if you're not handling your business then she will wander. Maybe not physically yet, but mentally.
Breh, fukk cheating, we're talking about life here. Whether she's getting dikked down by the basketball team or is wishy washy about being attracted to him or being with him that day, it's the same thing in my book. It's someone whose loyalty you can't trust.
And like I said, it doesn't make her a villain, it just gives him something to think about. I'm married. Me and my wife argue sometimes, don't see eye to eye all the time, but I know when we're talking about LIFE, and it's time to go into battle, that chick is right beside stabbing nikkas when she runs out of bullets and can't wait to reload and bust more shots at anybody and anything fukking with our union. That's how your woman has to be if you want to sleep good at night.
If you're in a serious relationship with someone who is wishy washy about you or their future with you, other than STDs, the end result is the same as cheating. The dude who made the Dwight Howard comparison hit the nail on the head. OP said they've been talking marriage. Spending your life with someone is no joke. Rather than ride the wave of her emotion, he needs to be thankful that she showed herself to be a hokie pokey one foot in, one foot out ass nikka before any rings were exchanged and names were changed.
This dude is about to be a doctor and start his empire. Why would he do that with a cornerstone that isn't solid, for WHATEVER reason.