Welcome! Not glad to see you in this sitch, but glad to see you looking for good advice.
Hmmm... DBing is about being willing to do the lion's share of the work for an unknown amount of time, with the knowledge that if it works, you'll end up reaping the rewards of your investment later in the new R. And if you don't end up together, you'll have changed in a very positive manner, thus benefiting regardless.
Pay attention to your H's request to take things slowly. Regardless, this will less "pressure" to be felt by your WAH. Don't dump your expectations for MC or a faster pace into the mix. That equals additional pressure.
Every time you feel frustrated or resentful or about to explode, use the space and time created by the slowed pace to douse yourself with self-care/self-love. Go workout, pick up old/new hobbies, make new friends, travel, get your nails or hair done, get a massage, soak in the tub with the candles on. If you do so in a disciplined fashion, you'll be more likely give off a "confidence" vibe when you are around him.
Finally, try your best to stay positive, upbeat, even playful around him. Positivity attracts folks while the opposite drives them away. Try also to remember the saying "Fake it til you make it." Even if you don't feel happy, act it, and over time, the GAL work will help you to actually get there.
There's lots of fodder from resentments in your sitch, and much data to lock him into the hopeless category (e.g., the ADD). You'll need to let that rigid way of perceiving things go, or your attempts to flexibly changed will be doomed by such thoughts.
Keep posting your efforts and their consequences, and we'll do our best to advise.
