I'm sure that the Lexapro hasn't appeared to make things any worse, but as you said....it probably isn't helping either. Out of curiosity....when it comes to his diet....who does the grocery shopping? I know in our home I'm the one who does the preponderance of it....there are certain things I just simply don't go buy. My H also drinks far too much soda.....now, when he wants it....he has to buy it. It obviously doesn't stop him from drinking it....but it does cut down the consumption I've noticed. I've also started keeping healthier snack foods in the house for him. Still stuff he likes, but the healthier alternatives. For example....my H is an ice-cream hound!!!! I found though that I could substitute his normally very high fat ice cream for a product called "All Fruit" it's like sherbert but with tons of fruit and high flavor.....he LOVES it!!! About the only two things I've found I can't substitute successfully are his potato chips and beer LOL.....but he has cut down on both. He recently had a bout with kidney stones....so he's seeing the benefit of changing his diet now. BUT...don't nag him about it.....that will only make him dig his heels in further and exhaust you. Nagging is a no-win situation.
What I mean by both of you getting to the Dr. is that I think you need to go to his Dr......with him for a visit, when he goes. I know with my H he's horrible about giving his Dr. the whole picture. There are many things he forgets to tell his Dr. or...simply thinks aren't important to tell him.....so often his Dr. doesn't get the gravity of the situation. If you go with him....then you can fill in the blanks.....you can also hear for yourself exactly what his Dr. tells him. That's what I meant.
Next...counseling. Ok, you need to remember you have control over YOUR behavior. If you find that things easily go the wrong direction when you try to broach something like counseling.....write him a letter. Read that letter over and over and over again....and make sure it doesn't sound like you are laying the blame for this situation directly at his feet. You need to try to keep the tone of your letter in the "I" perspective...."I feel", "I would like to go to counseling so we can.....", "I would like for us to......". Be very concious of not saying "you need to....." or "I need you to.....", that holds the danger of sounding like you are blaming him....or finding fault with him....stay away from it. If he's the type of person who would receive a letter well, give it to him.....with the statement of "please read this, and then lets discuss it later so I can hear your thoughts." If he doesn't receive letters well....then keep it with you when you have your next discussion to help draw you back to the topic at hand when things begin to get off track.
Now as for what type of counseling I'm talking about for you. Yes, I'd suggest the two of you find an excellent Marriage Counselor....one who can also see you both individually. One who specializes in marital issues. You can easily do a search on the internet for therapists in your area....many times they will list their specialties as well. Call some of them and do a brief phone interview to tell them your situation, let them know you are working to keep the marriage together, and ask what their style tends to be with couples. If someone won't take the time to talk with you....don't go to them. Some therapists obviously would need to call you back (that's what ours did)....if they truly do follow-up and call you back, that to me is a great indication that this is a therapist who cares.
And...yes, hold off on kids until you get this resolved. What do we mean by resolved? Either your H is going to learn how to work around his low libido and you two will come to a mutually agreeable place in your R where you are both giving.....or YOU will have to learn to live with the situation as is. You really need to put some thought into this question. "If my H is never able/willing to make the changes I need to feel satisfied sexually am I going to be able to live the rest of my life this way?" In other words....if things stay as they are, is it going to be a deal breaker for you in the future? Is this a way you can see yourself living for the rest of your life? If the answer is I don't know....or no, then DO NOT bring children in to the equation. You are still young, there is PLENTY of time for children. Having a child will not help the situation, a child will complicate it.
As I recall you mentioned earlier that you two waited to have sex until marriage. What is his history like? Any serious girlfriends prior to you? Any sexual activity that you know of prior to you? What are his parents like? Outwardly affectionate? Was he in an abusive home? Just throwing questions out there.....some history on him would truly help too. My H was raised in a strict home where affection just simply wasn't shown outwardly.....so he never really learned how to have a "loving" relationship. I'm having to draw that out of him....but he's improving. Just wanted you to know that. You are headed for A LOT of work....but honestly, it can pay off. I can testify to that. I came on here almost 3 years ago.....my M is lightyears better now than it was when I first got here.