There is only one thing worse than being in a bad marriage: being in a bad marriage with young children. It's FAR FAR FAR worse.
I know 34 makes you feel like the clocking is ticking fast, and I don't deny that it is but don't stay in this marriage so you can have kids with this fellow. Better to try something else (e.g., in vitro or adopt) later with someone else than try to force this to work.
Your H's relationship w/ his ex, as you described it, is entirely inappropriate. He should not be having regular meetings and texts with her, let alone secret ones.
Your subject line asks, "Not even married a year- hopeless?" I won't sugarcoat this. But the answer is yes. It's hopeless. I'm sorry. I just see far too much trouble in your marriage. There are people who show up here who have had 25 years of a good marriage, with young kids, sex and laughter every day for 25 years, and ... now they're here. You have been married a year.
But not all is lost. You can see this as a gift to your future self. Whatever you learn as you walk away from this wreckage can help you be in a far better place with your next relationship. Do some soul searching about how you chose the man you did. Why were you drawn to this person? Why didn't you see the fatal flaws you see now? How did you react poorly to problems?
If your H were to post here, what are the worst accusations and complaints he would have of you? Whether or not they are true, you could use those criticisms to examine yourself, and see if there is room for improvement, to be a healthier future partner for someone else.
Sorry for the bad news. I'm just calling it as I see it. We are all in deep pain here.
Me: 50, MLC/WW 45 Young kids Nov 2015: BD1 Apr 2016: BD2 Jan 2017: W filed Feb 2017: D final