Luckily, Molly had John Watson as an ally.
"What's going on, Sherlock?"
"Nothing is going on."
"Right. How about the truth?"
Sherlock sighed. "Mycroft isn't going to stop seeing Molly."
"And?"
"And? Isn't that enough? She's choosing to spend her time with...Mycroft, of all people," he nearly choked on his words.
"You need to stop this right now. Go & tell Molly what's going on. And before you do that, you need to figure out what the hell is going on with you. Is this sibling rivalry, or do you honestly care about her?"
Sherlock looked at him. He knew that John was right. It was most unfair for him to be behaving in such a horrid manner. He was ashamed. He was embarrassed. He was wrong, & he hated that.
He put his coat on & left the flat. He would go see Molly & apologize.

Molly was cleaning her instruments when she felt the hand on her shoulder & she screamed.
"Sherlock! What are you doing?"
"I'm sorry."
"Ok. It's ok." She looked at him. "Er...what do you need?"
"Just that. I'm sorry. I've been harboring some ill feelings (he grimaced) about your friendship with Mycroft. I'm sorry."
"Ill feelings? You mean jealousy?"
"Well, in a matter of speaking."
Molly smiled. "And what has Mycroft to say on the matter?"
"He refused to satisfy my pleas to leave you alone," Sherlock shuffled his feet & put his hands in his pockets.
"Oh." She honestly didn't know what to say. "Well, I'm glad, I enjoy his company."
"How much?"
"Sorry, what?"
"How much do you...enjoy his company?"
He looked steadily at her. She wavered under his gaze. "I dunno, Sherlock. Why? It's not like I won't let you lose the lab simply because I have coffee with your brother."
"I see."
"You do? Because I have no idea."
At that, he grabbed her arm & kissed her mouth. He pulled away & left the lab. Molly stood there, confused, overwhelmed, & angry.

His PA rang the phone. It seemed to be mocking him, since he was so useless today. He was distracted. He was uneasy. He hated himself for it.
"A Molly Hooper is here to see you," rang out her voice in the otherwise still office.
"Have her come in." Mycroft stood. He had been expecting this.
Molly walked in & stomped right over to the desk where Mycroft Holmes stood opposite.
"Explain to me why your brother is so jealous that he just came to my work, apologized to me & snogged me."
"Excuse me?"
"I think you heard me, Mycroft, Sherlock is jealous. Why?"
"I'm sorry, Molly. I haven't the faintest. Perhaps he's concerned that he will require you to fetch & carry for him when you're sharing coffee with me."
Molly smiled at this. "Have you given him any reason to be jealous?"
"Not that I'm aware of. I certainly never intended to, as such."
"You are fully aware of my feelings for him. Did you persuade him at all?" Molly was suspicious. Mycroft was a Holmes, after all.
"No. Not even slightly."
"Ok. Well. It seems that my dreams have been answered. Sherlock Holmes fancies me." She didn't sound nearly as jubilant as she would've thought.
"It would appear so, yes."
"You knew, didn't you?"
"I suspected. Though he never admitted anything to me," Mycroft was looking out of the window. "You should go to him, Molly. Tell him you reciprocate his feelings."
"Yes..." Molly smiled. "Thanks, Mycroft. I'm going to do just that." And she left.
He was still smiling absently after she had gone. He knew how things would be. He knew that Sherlock would wish to posses all of her time. And that would be the end of that.

His heart ached a bit. He went home early to tend to his violin. He wished he possessed something that would quell the misery that welled inside of him. So foreign a state for a man of his age. He noted the silliness of it, & the ridiculous nature of so many people spending so much of their time thus. Feelings, indeed. Weakness, more like it. He would spend the night feeling the loss wholly, & in the morning, he would be a new man. He didn't need any pathologist to make him feel content, smiling eyes & a warm heart notwithstanding.