They said "I love you"

In a nutshell, I (42F) found out early November that my WH (42M) had two affairs. One was 7 years ago that was physical and lasted about a month (with continued "friendly" conversation until D day). The second was an emotional affair (with the exchange of pics) that lasted three years and was still ongoing up until 2 days post D Day. Both affairs happened while we were married (together 22 years, married for 10). We are both in therapy and have started the full disclosure process. He is engaged in my healing, accepts full responsibility for his actions (which are due to internal issues), and is patient (almost always) in answering my many repeated questions. I never thought betrayal would hit me like this. Words can't describe it.

There are two things that I'm struggling the most with (amongst a thousand others) and would love some advice from both WS and BS:

He told her "I love you" - this hurts so deep. I know logically their relationship was not love. It was mainly through text and toxic. They would go through periods where they would block each other. She was in a relationship too. There was no real life happening, neither really knew the other person. Yet, as much as I understand that, knowing he spoke those words to another woman breaks me.

• WS - if you said "I love you" to your AP, what did that mean to you? Did you really believe it at the time?
• BS - if your WS said "I love you" to their AP, how did you cope and move past that?

The longevity. So many opportunities to stop the relationships and do right by our marriage. Sure, our relationship wasn't perfect (noone's is) but it still was a great relationship (a close friend even said when finding out - "I don't understand - you guys don't have this horrible relationship") and going back and cross referencing affair event dates to photos in my phone is heartbreaking. Confirming "We had a great day that day. We were so happy that day."

• WS - did you ever seriously consider your spouse during that long stretch? Did happy times with your spouse ever make you want to end the affair? If so, why didn't you?
• BS - how do you cope with how long the affair lasted? I feel like there are so many years stolen from me and that time living in deceit is something I can never get back. All those years and all that opportunity to end things... it's hard to know that I never mattered more than his demons once, or enough to stop, during that long stretch of time.