Talking/Initiating Sex

My wife and I haven't had sex or any sexual contact in several months. We have had similar issues in the past due to her stress or feeling bad about herself due to body issues. Prior to this I felt like we had a pretty good sex life, it was frequent and we would try new things. I was very open to talking about sex and initiate often. Things changed when she had gained weight due to a medical issue and no longer felt comfortable showing herself in front of me even though I still thought she looked wonderful and told her so often. At this point our sex life started to dwindle and I stopped trying to initiate because I was so tired of being rejected all the time. Eventually the only time we would have sex only was when trying to conceive and it was no longer fun or enjoyable. After having kids and my wife was able to get herself back to a body image she was comfortable with but we were so busy and tired all the time we no longer found the time to do anything. Plus my wife became very stressed due to work and other life issues. It came down to us maybe having sex a few times a year. Early last year we had a deep discussion about our lacking sex life and she also inquired about how often I masturbated and of my porn use and she said she was okay with it all but just doesn't want to know about it. We decided to start trying to make more time for ourselves and we started having more frequent sex, similar to how we used to but I was still having trouble initiating because of fear of rejection. We got pregnant and her hormones took off and she couldn't get enough things were going great. Later into pregnancy we decided to have a weekend getaway before the baby arrived. All weekend I tried initiating and she turned me down saying she wasn't in the mood or too tired. This hurt my ego a bit since this had been really my first big attempt at outwardly initiating since being rejected so many times before but I just shook it off. When we got home things went back to the hustle of daily life. The following weekend I tried to initiate once again but this time she turned me down and said she was no longer interested. Fast forward several months later and well past birth we still haven't had any sexual contact. She has mentioned a few times she is now ready to start again but usually not in a good time when we can. We have both been very tired with taking care of a newborn and other children and she often falls asleep early leaving me alone to fend for myself. I really want to try initating again but I'm also afraid of being rejected and never know when is a good time because she never seems in the mood until the most inconvenient times. I also worry she will think if I don't do anything that I no longer want her which isn't the case at all.

Tldr: Wife's frequent rejection in the past leaves me anxious about initiating now.