Morgan and Faith ran into each other on occasion at various places. They're initial meeting (many years ago) took place at restaurant where they were both with their families. Beverly told Faith, "Your future husband is sitting over there" gesturing to a table behind them where Morgan was. Faith looked and told her mom "Whatever."
After a surprise birthday party thrown for Max, Morgan messaged Faith later that night asking her to go dinner the following weekend "celebrating being done with midterms," which obviously was not the real reason he wanted to take her out. To no surprised, she said yes to a couple hours at Cinergy and Outback.
The answer may vary depending on who you ask, but Morgan mostly initiated it after a few moths of dating, but he also makes fun of Faith for how she responded (to which she will not talk about). They would both agree it had been a thought on both their minds quite for a while.
Morgan began planning a proposal for a little over month. They went to dinner and then headed to Palo Duro Canyon where he popped the question.