What to do when he’s lost that loving feeling

Me and my husband have been TTC on and off for about 8 of the 12 years we’ve been together, almost 2 years married. When we started this journey, we were both healthier, and weighed a lot less. Even with the weight gain (as we grew more comfortable with each other and life got a little crazier and we got a little more lax), we were still “trying” a handful of nights out of the week, and we couldn’t keep our hands off each other. I feel like in the past year of TTC, we really don’t have sex much anymore since he’s too tired or when we do try, he can’t finish. We are also both on antidepressants, I’m not sure if his are the reason why he has no urge, even though he assures me he has sexual thoughts about me. He also has a low sperm count (and since finding that out, we have sex even less.) I’m not sure if there’s anything I could be doing to help him get the urge back, or if this is a “normal” marriage thing or a weird phase, or because of the meds. Any advice?